71M6513H-DB

71M6513/71M6513H Demo Board USER’S MANUAL 4/9/2007 10:06 AM Revision 5.6 TERIDIAN Semiconductor Corporation 6440 Oak Canyon Rd. Irvine, CA 92618-5201 Phone: (714) 508-8800 ▪ Fax: (714) 508-8878 http://www.teridian.com/ meter.support@teridian.com 71M6513/71M6513H Demo Board User’s Manual TERIDIAN Semiconductor Corporation makes no warranty for the use of its products, other than expressly contained in the Company’s warranty detailed in the TERIDIAN Semiconductor Corporation standard Terms and Conditions. The company assumes no responsibility for any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice and does not make any commitment to update the information contained herein. Page: 2 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 71M6513/71M6513H 3-Phase Energy Meter IC DEMO BOARD USER’S MANUAL Page: 3 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Table of Contents 1 GETTING STARTED.............................................................................................................................................. 9 1.1 General .................................................................................................................................................................. 9 1.2 Safety and ESD Notes .......................................................................................................................................... 9 1.3 Demo Kit Contents ............................................................................................................................................. 10 1.4 Demo Board Versions ........................................................................................................................................ 10 1.5 Compatibility....................................................................................................................................................... 10 1.6 Suggested Equipment not Included ................................................................................................................. 10 1.7 Demo Board Test Setup..................................................................................................................................... 11 1.7.1 Power Supply Setup ...................................................................................................................................... 14 1.7.2 Cable for Serial Connection (Debug Board) .................................................................................................. 14 1.7.3 Checking Operation....................................................................................................................................... 14 1.7.4 Serial Connection Setup................................................................................................................................ 15 1.8 Using the Demo Board....................................................................................................................................... 16 1.8.1 Serial Command Language........................................................................................................................... 17 1.8.2 Using the Demo Board for Energy Measurements ........................................................................................ 26 1.8.3 Adjusting the Kh Factor for the Demo Board ................................................................................................. 26 1.8.4 Adjusting the Demo Boards to Different Current Transformers ..................................................................... 27 1.8.5 Adjusting the Demo Boards to Different Voltage Dividers ............................................................................. 27 1.9 Calibration Parameters ...................................................................................................................................... 28 1.9.1 General Calibration Procedure ...................................................................................................................... 28 1.9.2 Calibration Macro File ................................................................................................................................... 29 1.9.3 Updating the 6513_demo.hex file.................................................................................................................. 29 1.9.4 Updating Calibration Data in Flash Memory without Using the ICE or a Programmer................................... 29 1.9.5 Automatic Gains Calibration .......................................................................................................................... 30 1.9.6 Loading the 6513_demo.hex file into the Demo Board.................................................................................. 30 1.9.7 The Programming Interface of the 71M6513/6513H ..................................................................................... 32 1.10 Demo Code...................................................................................................................................................... 33 1.10.1 Demo Code Description............................................................................................................................. 33 1.10.2 Demo Code MPU Parameters ................................................................................................................... 34 1.10.3 Useful CLI Commands Involving the MPU and CE.................................................................................... 40 1.10.4 Demo Code for Neutral Detection (Demo Board D6513T3C1) .................................................................. 40 2 APPLICATION INFORMATION ........................................................................................................................... 43 2.1 Calibration Theory.............................................................................................................................................. 43 2.1.1 Calibration with Three Measurements ........................................................................................................... 43 2.1.2 Calibration with Five Measurements.............................................................................................................. 45 2.2 Calibration Procedures ...................................................................................................................................... 46 2.2.1 Calibration Procedure with Three Measurements ......................................................................................... 47 2.2.2 Calibration Procedure with Five Measurements ............................................................................................ 48 2.2.3 Calibration Procedure for Rogowski Coil Sensors ......................................................................................... 48 2.2.4 Calibration Spreadsheets .............................................................................................................................. 49 2.2.5 Compensating for Non-Linearities ................................................................................................................. 53 Page: 4 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.3 Power Saving Measures .................................................................................................................................... 54 2.4 Schematic Information....................................................................................................................................... 55 2.4.1 Components for the V1 Pin ........................................................................................................................... 55 2.4.2 Reset Circuit.................................................................................................................................................. 55 2.4.3 Oscillator ....................................................................................................................................................... 56 2.4.4 EEPROM....................................................................................................................................................... 56 2.4.5 LCD ............................................................................................................................................................... 57 2.4.6 Optical Interface ............................................................................................................................................ 58 2.4.7 Connecting the RX Pin .................................................................................................................................. 59 2.4.8 Connecting the V3 Pin................................................................................................................................... 60 2.5 Testing the Demo Board .................................................................................................................................... 61 2.5.1 Functional Meter Test.................................................................................................................................... 61 2.5.2 EEPROM....................................................................................................................................................... 62 2.5.3 RTC............................................................................................................................................................... 63 2.5.4 Hardware Watchdog Timer............................................................................................................................ 63 2.5.5 LCD ............................................................................................................................................................... 63 2.6 TERIDIAN Application Notes ............................................................................................................................. 64 3 HARDWARE DESCRIPTION............................................................................................................................... 65 3.1 D6513T3B2 Board Description: Jumpers, Switches and Test Points............................................................ 65 3.2 D6513T3C1 Board Description: Jumpers, Switches and Test Points............................................................ 69 3.3 D6513T3D2 Board Description: Jumpers, Switches and Test Points............................................................ 72 3.4 Board Hardware Specifications (D6513T3B2, D6513T3C1)............................................................................. 75 3.5 Board Hardware Specifications (D6513T3D2).................................................................................................. 76 4 APPENDIX ........................................................................................................................................................... 77 List of Figures Figure 1-1: TERIDIAN D6513T3B2 Demo Board with Debug Board: Basic Connections ................................................. 11 Figure 1-2: Block diagram for the TERIDIAN D6513T3B2 Demonstration Meter with Debug Board................................. 12 Figure 1-3: Block diagram for the TERIDIAN D6513T3C1 and D6513T3D2 Demo Boards with Debug Board ................. 13 Figure 1-4: Hyperterminal Sample Window with Disconnect Button (Arrow) ..................................................................... 15 Figure 1-5: Port Speed and Handshake Setup (left) and Port Bit setup (right).................................................................. 16 Figure 1-6: Command Line Help Display........................................................................................................................... 17 Figure 1-7: Typical Calibration Macro file .......................................................................................................................... 29 Figure 1-8: Emulator Window Showing Reset and Erase Buttons (see Arrows) ............................................................... 31 Figure 1-9: Emulator Window Showing Erased Flash Memory and File Load Menu ......................................................... 31 Figure 2-1: Watt Meter with Gain and Phase Errors.......................................................................................................... 43 Figure 2-2: Phase Angle Definitions .................................................................................................................................. 47 Figure 2-3: Calibration Spreadsheet for Three Measurements ......................................................................................... 51 Figure 2-4: Calibration Spreadsheet for Five Measurements ............................................................................................ 51 Figure 2-5: Calibration Spreadsheet for Rogowski coil...................................................................................................... 52 Figure 2-6: Non-Linearity Caused by Quantification Noise................................................................................................ 53 Figure 2-7: Voltage Divider for V1 ..................................................................................................................................... 55 Figure 2-8: External Components for RESETZ ................................................................................................................. 55 Page: 5 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Figure 2-9: Oscillator Circuit.............................................................................................................................................. 56 Figure 2-10: EEPROM Circuit ........................................................................................................................................... 56 Figure 2-11: LCD Connections.......................................................................................................................................... 57 Figure 2-12: LCD Boost and LCD Control Registers ......................................................................................................... 57 Figure 2-13: Optical Interface Block Diagram.................................................................................................................... 58 Figure 2-14: Optical Port Circuitry on the D6513T3B2 Demo Board ................................................................................. 58 Figure 2-15: Optical Port Circuitry on the D6513T3C1 Demo Board ................................................................................. 59 Figure 2-16: Internal Diode Clamp on the RX Pin ............................................................................................................. 59 Figure 2-17: Resistor Network for RX................................................................................................................................ 60 Figure 2-18: Meter with Calibration System ...................................................................................................................... 61 Figure 2-19: Calibration System Screen............................................................................................................................ 62 Figure 3-1: D6513T3B2 Demo Board - Board Description (Default jumper settings indicated in yellow)........................... 68 Figure 3-2: D6513T3C1 Demo Board - Board Description ................................................................................................ 71 Figure 3-3: D6513T3D2 Demo Board - Board Description ................................................................................................ 74 Figure 4-1: TERIDIAN D6513T3B2 Demo Board: Electrical Schematic 1/3 ...................................................................... 78 Figure 4-2: TERIDIAN D6513T3B2 Demo Board: Electrical Schematic 2/3 ...................................................................... 79 Figure 4-3: TERIDIAN D6513T3B2 Demo Board: Electrical Schematic 2/3 ...................................................................... 80 Figure 4-4: TERIDIAN D6513T3C1 Demo Board: Electrical Schematic 1/3...................................................................... 81 Figure 4-5: TERIDIAN D6513T3C1 Demo Board: Electrical Schematic 2/3...................................................................... 82 Figure 4-6: TERIDIAN D6513T3C1 Demo Board: Electrical Schematic 3/3...................................................................... 83 Figure 4-7: TERIDIAN D6513T3D2 Demo Board: Electrical Schematic 1/3...................................................................... 84 Figure 4-8: TERIDIAN D6513T3D2 Demo Board: Electrical Schematic 2/3...................................................................... 85 Figure 4-9: TERIDIAN D6513T3D2 Demo Board: Electrical Schematic 3/3...................................................................... 86 Figure 4-10: TERIDIAN D6513T3B2 Demo Board: Top View ........................................................................................... 90 Figure 4-11: TERIDIAN D6513T3B2 Demo Board: Bottom View ...................................................................................... 91 Figure 4-12: TERIDIAN D6513T3B2 Demo Board: Top Signal Layer ............................................................................... 92 Figure 4-13: TERIDIAN D6513T3B2 Demo Board: Middle Layer 1 (Ground Plane) ......................................................... 93 Figure 4-14: TERIDIAN D6513T3B2 Demo Board: Middle Layer 2 (Supply Plane) .......................................................... 94 Figure 4-15: TERIDIAN D6513T3B2 Demo Board: Bottom Signal Layer .......................................................................... 95 Figure 4-16: TERIDIAN D6513T3C1 Demo Board: Top View ........................................................................................... 96 Figure 4-17: TERIDIAN D6513T3C1 Demo Board: Bottom View...................................................................................... 97 Figure 4-18: TERIDIAN D6513T3C1 Demo Board: Top Signal Layer ............................................................................... 98 Figure 4-19: TERIDIAN D6513T3C1 Demo Board: Ground Plane Layer .......................................................................... 99 Figure 4-20: TERIDIAN D6513T3C1 Demo Board: Power Plane Layer.......................................................................... 100 Figure 4-21: TERIDIAN D6513T3C1 Demo Board: Bottom Signal Layer........................................................................ 101 Figure 4-22: TERIDIAN D6513T3D2 Demo Board: Top Signal Layer ............................................................................. 102 Figure 4-23: TERIDIAN D6513T3D2 Demo Board: Bottom Signal Layer........................................................................ 103 Figure 4-24: TERIDIAN D6513T3D2 Demo Board: Bottom View.................................................................................... 104 Page: 6 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Figure 4-25: Debug Board: Electrical Schematic............................................................................................................. 106 Figure 4-26: Debug Board: Top View.............................................................................................................................. 107 Figure 4-27: Debug Board: Bottom View......................................................................................................................... 107 Figure 4-28: Debug Board: Top Signal Layer.................................................................................................................. 108 Figure 4-29: Debug Board: Middle Layer 1 (Ground Plane) ............................................................................................ 108 Figure 4-30: Debug Board: Middle Layer 2 (Supply Plane) ............................................................................................. 109 Figure 4-31: Debug Board: Bottom Trace Layer ............................................................................................................. 109 Figure 4-32: TERIDIAN 71M6513/71M6513H epLQFP100: Pinout (top view) ................................................................ 112 List of Tables Table 1-1: Jumper settings on Debug Board..................................................................................................................... 14 Table 1-2: Straight cable connections ............................................................................................................................... 14 Table 1-3: Null-modem cable connections ........................................................................................................................ 14 Table 1-4: CE RAM Locations for Calibration Constants................................................................................................... 28 Table 1-5: Flash Programming Interface Signals .............................................................................................................. 32 Table 1-6: MPU Input Parameters for Metering................................................................................................................. 35 Table 1-7: MPU Input Parameters for Temperature Compensation .................................................................................. 35 Table 1-8: MPU Parameters for Pulse Source Selection................................................................................................... 36 Table 1-9: Selectable Pulse Sources ................................................................................................................................ 36 Table 1-10: MPU Instantaneous Output Variables ............................................................................................................ 37 Table 1-11: MPU Status Word Bit Assignment.................................................................................................................. 38 Table 1-12: MPU Accumulation Output Variables ............................................................................................................. 39 Table 1-13: CLI Commands for MPU Data Memory.......................................................................................................... 40 Table 1-14: Neutral Current Accuracy at Various Sampling Frequencies ......................................................................... 41 Table 2-1: Power Saving Measures .................................................................................................................................. 54 Table 3-1: D6513T3B2 Demo Board Description .............................................................................................................. 65 Table 3-2: D6513T3B2 Demo Board Description .............................................................................................................. 66 Table 3-3: D6513T3B2 Demo Board Description .............................................................................................................. 67 Table 3-4: D6513T3C1 Demo Board Description.............................................................................................................. 69 Table 3-5: D6513T3C1 Demo Board Description.............................................................................................................. 70 Table 3-6: D6513T3D2 Demo Board Description.............................................................................................................. 73 Table 4-1: D6513T3C1 Demo Board: Bill of Material ........................................................................................................ 87 Table 4-2: D6513T3B2 Demo Board: Bill of Material ........................................................................................................ 88 Table 4-3: D6513T3D2 Demo Board: Bill of Material ........................................................................................................ 89 Table 4-4: Debug Board: Bill of Material.......................................................................................................................... 105 Table 4-5: 71M6513/71M6513H Pin Description Table 1/3............................................................................................. 110 Table 4-6: 71M6513/71M6513H Pin Description Table 2/3............................................................................................. 110 Table 4-7: 71M6513/71M6513H Pin Description Table 3/3............................................................................................. 111 Page: 7 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Page: 8 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1 1 GETTING STARTED 1.1 GENERAL The TERIDIAN Semiconductor Corporation (TSC) 71M6513/71M6513H Demo Board is a demonstration board for evaluating the 71M6513/71M6513H device for 3-phase electronic power metering applications. It incorporates a 71M6513 or 71M6513H integrated circuit, peripheral circuitry such as a serial EEPROM, emulator port, and on board power supply as well as a companion Debug Board that allows a connection to a PC through a RS232 port. The demo board allows the evaluation of the 71M6513 or 71M6513H energy meter chip for measurement accuracy and overall system use. The board is pre-programmed with a Demo Program (file name 6513_demo.hex) in the FLASH memory of the 71M6513/6513H IC. This embedded application is developed to exercise all low-level function calls to directly manage the peripherals, flash programming, and CPU (clock, timing, power savings, etc.). The 71M6513/6513H IC on the Demo Board is pre-programmed with default calibration factors. 1.2 SAFETY AND ESD NOTES Connecting live voltages to the demo board system will result in potentially hazardous voltages on the demo board. BEFORE OPERATING THE DEMO BOARD, THE JUMPERS ON JP2 AND JP3 (IF INSTALLED) SHOULD BE REMOVED! IT IS RECOMMENDED TO OPERATE THE DEBUG BOARD WITH ITS OWN POWER SUPPLY. THE DEMO SYSTEM IS ESD SENSITIVE! ESD PRECAUTIONS SHOULD BE TAKEN WHEN HANDLING THE DEMO BOARD! EXTREME CAUTION SHOULD BE TAKEN WHEN HANDLING THE DEMO BOARD ONCE IT IS CONNECTED TO LIVE VOLTAGES! Page: 9 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.3 DEMO KIT CONTENTS • Demo Board with 71M6513/71M6513H IC and pre-loaded demo program: • D6513T3B2 Demo Board (standard poly-phase), or • D6513T3C1 Demo Board (poly-phase w/ added neutral current capability) • Debug Board • Two 5VDC/1,000mA universal wall transformers with 2.5mm plug (Switchcraft 712A compatible) • Serial cable, DB9, Male/Female, 2m length (Digi-Key AE1020-ND) • CD-ROM containing documentation (data sheet, board schematics, BOM, layout), Demo Code (sources and executable), and utilities The CD-ROM contains a file named readme.txt that specifies all files found on the media and their purpose. 1.4 DEMO BOARD VERSIONS The following versions of the Demo Board are available: 1.5 • Demo Board D6513T3B2 (standard) • Demo Board D6513T3C1 (with neutral current detection capability) • Demo Board D6513T3D2 (two layer PCB, with neutral current detection capability) COMPATIBILITY This manual applies to the following hardware and software revisions: 1.6 • 71M6513 or 71M6513H chip revision B03 • Demo Kit firmware revision 3.04 and 3.05 or later • Demo Boards D6513T3B2, D6513T3C1 and D6513T3D2 SUGGESTED EQUIPMENT NOT INCLUDED For functional demonstration: • PC w/ MS-Windows versions XP, ME, or 2000, equipped with RS232 port (COM port) via DB9 connector For software development (MPU code): • Signum ICE (In Circuit Emulator): ADM-51 http://www.signum.com • Keil 8051 “C” Compiler kit: CA51 http://www.keil.com/c51/ca51kit.htm, http://www.keil.com/product/sales.htm Page: 10 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.7 DEMO BOARD TEST SETUP Figure 1-1 shows the basic connections of the Demo Board plus Debug Board with the external equipment for desktop testing, i.e. without live power applied. For desktop testing, both the Demo and Debug board may be powered with just the 5VDC power supplies. Power Demo Board Power Supply (100 to 240VAC, 1ADC Output) Debug Board Power Host PC Figure 1-1: TERIDIAN D6513T3B2 Demo Board with Debug Board: Basic Connections The D6513/T3B2 Demo Board block diagram is shown in Figure 1-2. It consists of a stand-alone (round) meter Demo Board and an optional Debug Board. The Demo Board contains all circuits necessary for operation as a meter, including display, calibration LED, and internal power supply. The Debug Board, when using a separate power supply, is optically isolated from the meter and interfaces to a PC through a 9 pin serial port. For serial communication between the PC and the TERIDIAN 71M6513/71M6513H, the Debug Board needs to be plugged with its connector J3 into connector J2 of the Demo Board. The D6513/T3C1 Demo Board System is shown in Figure 1-3. It is almost identical to the D6513T3B2, except that the neutral current input is added and the optional power and ground connections from the Demo Board to the Debug Board were removed. Connections to the external signals to be measured, i.e. scaled AC voltages and current signals derived from shunt resistors or current transformers, are provided on the rear side of the demo board. Caution: It is recommended to set up the demo board with no live AC voltage connected, and to connect live AC voltages only after the user is familiar with the demo system. Page: 11 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual DEMONSTRATION METER 6513 Single Chip Meter DIO6 External Current Transformers IA IA DIO7 VAR PULSE OUTPUTS V3P3 V3P3 5V LCD DISPLAY IB IB WATT IC IC V3P3 VC VB VA DIO4 DIO5 EEPROM ICE Connector VA VB VC JP1 MPU HEARTBEAT (5Hz) DIO0 V3P3 NEUT DEBUG BOARD (OPTIONAL) 3.3v DIO1 GND 5V DC GND JP3 CE HEARTBEAT (1Hz) V5_DBG OPTO CYCLE DISPLAY DIO2 TX JP2 V5_DBG OPTO RX OPTO OPTO GND_DBG V5_DBG DB9 to PC COM Port RS-232 INTERFACE OPTO OPTO SUPPLY RTM INTERFACE TMUXOUT J5 OPTO FPGA CKTEST 68 Pin Connector to NI PCI-6534 DIO Board OPTO V5_DBG OPTO SUPPLY 5V DC V5_NI GND_DBG Figure 1-2: Block diagram for the TERIDIAN D6513T3B2 Demonstration Meter with Debug Board All input signals are referenced to the V3P3 (3.3V power supply to the chip). Page: 12 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual DEMONSTRATION METER External Current Transformers PULSE OUTPUTS V3 INEUTRAL VBIAS IA IA DIO6 DIO7 6513 Single Chip IC Meter DIO4 V3P3 DIO5 IC VC VB VA VAR V3P3 V3P3 5V LCD DISPLAY IB IB WATT EEPROM ICE Connector VA VB VC JP1 3.3v DIO1 GND 5V DC MPU HEARTBEAT (5Hz) DIO0 V3P3 NEUT DEBUG BOARD (OPTIONAL) GND OPTO V5_DBG CE HEARTBEAT (1Hz) V5_DBG OPTO CYCLE DISPLAY DIO2 TX RX OPTO OPTO GND_DBG V5_DBG DB9 to PC COM Port RS-232 INTERFACE OPTO OPTO SUPPLY TMUXOUT J5 OPTO CKTEST OPTO V5_DBG FPGA (optional) 68 Pin Connector to NI PCI-6534 DIO Board OPTO SUPPLY V5_NI 5V DC GND_DBG OPTIONAL RTM INTERFACE Figure 1-3: Block diagram for the TERIDIAN D6513T3C1 and D6513T3D2 Demo Boards with Debug Board Page: 13 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.7.1 POWER SUPPLY SETUP There are several choices for meter power supply: • Internal (using phase A of the AC line voltage). The internal power supply is only suitable when phase A exceeds 220V RMS. • External 5VDC connector (J1) on the Demo Board • External 5VDC connector (J1) on the Debug Board. The three power supply jumpers, JP1, JP2, and JP3 (JP2/JP3 is only provided on the D6513T3B2 Demo Board), must be consistent with the power supply choice. JP1 connects the AC line voltage to the internal power supply. This jumper should usually be left in place. JP2 and JP3 should be left open (unconnected). 1.7.2 CABLE FOR SERIAL CONNECTION (DEBUG BOARD) For connection of the DB9 serial port to a PC, either a straight or a so-called “null-modem” cable may be used. JP1 and JP2 are plugged in for the straight cable, and JP3/JP4 are empty. The jumper configuration is reversed for the null-modem cable, as shown in Table 1-1. Cable Configuration Mode Straight Cable Null-Modem Cable Jumpers on Debug Board JP1 JP2 JP3 JP4 Default Installed Installed -- -- Alternative -- -- Installed Installed Table 1-1: Jumper settings on Debug Board JP1 through JP4 can also be used to alter the connection when the PC is not configured as a DCE device. Table 1-2 shows the connections necessary for the straight DB9 cable and the pin definitions. PC Pin Function Demo Board Pin 2 TX 2 3 RX 3 5 Signal Ground 5 Table 1-2: Straight cable connections Table 1-3 shows the connections necessary for the null-modem DB9 cable and the pin definitions. PC Pin Function Demo Board Pin 2 TX 3 3 RX 2 5 Signal Ground 5 Table 1-3: Null-modem cable connections 1.7.3 CHECKING OPERATION A few seconds after power up, the LCD display on the Demo Board should display this brief greeting: H Page: 14 of 112 E L L 0 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual The “HELLO” message should be followed by the display of accumulated energy: 3. 0. 0 0 1 The decimal dot in the leftmost segment will be blinking, indicating activity of the MPU inside the 71M6513/6513H. If contacts 3 and 5 of J2 are shorted with a jumper (or if the “DISPLAY SEL” switch SW2 on the Debug Board is pressed and held down), the display will show a series of incrementing numbers (1 through 12) in the leftmost digit(s) followed by the default date (2001.01.01) at number 10. Once, the Debug Board is plugged into J2 of the Demo Board, LED DIO1 on the Debug Board will flash with a frequency of 1Hz, indicating CE activity. The LED DIO0 will flash with a frequency of 5Hz, indicating MPU activity. 1.7.4 SERIAL CONNECTION SETUP After connecting the DB9 serial port to a PC, start the HyperTerminal application and create a session using the following parameters: Port Speed: 9600 baud Data Bits: 8 Parity: None Stop Bits: 1 Flow Control: XON/XOFF HyperTerminal can be found by selecting Programs ÆAccessories Æ Communications from the Windows start menu. The connection parameters are configured by selecting File Æ Properties and then by pressing the Configure button. Port speed and flow control are configured under the General tab (Figure 1-5, left), bit settings are configured by pressing the Configure button (Figure 1-6, right), as shown below. A setup file (file name “Demo Board Connection.ht”) for HyperTerminal that can be loaded with File Æ Open is also provided with the tools and utilities. Port parameters can only be adjusted when the connection is not active. The disconnect button, as shown in Figure 1-4 must be clicked in order to disconnect the port. Figure 1-4: Hyperterminal Sample Window with Disconnect Button (Arrow) Page: 15 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Figure 1-5: Port Speed and Handshake Setup (left) and Port Bit setup (right) Once, the connection to the demo board is established, press and the prompt, >, should appear. Type >? to see the Demo Code help menu. Type >i1 to verify that the demo code revision is 3.04 or later. 1.8 USING THE DEMO BOARD The 71M6513/6513H Demo Board is a ready-to-use meter prepared for use with an external current transformer. Using the Demo Board involves communicating with the Demo Code via the command line interface (CLI). The CLI allows all sorts of manipulations to the metering parameters, access to the EEPROM, initiation of auto-cal sequences, selection of the displayed parameters, changing calibration factors and many more operations. Before evaluating the 71M6513/6513H on the Demo Board, users should get familiar with the commands and responses of the CLI. A complete description of the CLI is provided in section 1.8.1. Page: 16 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.8.1 SERIAL COMMAND LANGUAGE The Demo Code residing in the flash memory of the 71M6513/6513H provides a convenient way of examining and modifying key meter parameters. Once the Demo Board is connected to a PC or terminal per the instructions given in Section 1.7.2 and 1.7.4, typing ‘?’ will bring up the list of commands shown in Figure 1-6. Figure 1-6: Command Line Help Display The tables in this chapter describe the commands in detail. Demo Code revision 3.05 offers more commands than revision 3.04. Commands only available on 3.05 are marked in the tables presented in this chapter. Page: 17 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands to Display Help on the CLI Commands: ? HELP Description: Command help available for each of the options below. Command combinations: ? Command line interpreter help menu. ?] Display help on access CE data RAM ?) Display help on access MPU RAM ?, Display help on repeat last command ?/ Display help on ignore rest of line ?C Display help on compute engine control and calibration. In 3.05, pulse counter functions are offered. ?EE Display help on EEPROM control ?I Display help on information message ?M Display help on meter display control ?P Display help on profile of meter ?R Display help on SFR control ?RT Display help on RTC control ?T Display help on trim control ?W Display help on the wait/reset command – 3.05 only ?Z Display help on reset ?? Display the command line interpreter help menu. ?C Displays compute engine control help. Examples: Commands for CE Data Access: ] CE DATA ACCESS Description: Allows user to read from and write to CE data space. Usage: ] [Starting CE Data Address] [option]…[option] Command combinations: ]A??? Read consecutive 16-bit words in Decimal, starting at address A ]A$$$ Read consecutive 16-bit words in Hex, starting at address A ]A=n=n Write consecutive memory values, starting at address A ]U Update default version of CE Data in flash memory ]40$$$ Reads CE data words 0x40, 0x41 and 0x42. ]7E=12345678=9876ABCD Writes two words starting @ 0x7E Example: CE data space is the address range for the CE DRAM (0x1000 to 0x13FF). All CE data words are in 4-byte (32bit) format. The offset of 0x1000 does not have to be entered when using the ] command, thus typing ]A? will access the 32-bit word located at the byte address 0x1000 + 4 * A = 0x1028. Page: 18 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for MPU/XDATA Access: ) MPU DATA ACCESS Description: Allows user to read from and write to MPU data space. Usage: ) [Starting MPU Data Address] [option]…[option] Command combinations: )A??? Read three consecutive 32-bit words in Decimal, starting at address A )A$$$ Read three consecutive 32-bit words in Hex, starting at address A )A=n=m Write the values n and m to two consecutive addresses starting at address A )08$$$$ Reads data words 0x08, 0x0C, 0x10, 0x14 )04=12345678=9876ABCD Writes two words starting @ 0x04 Example: MPU or XDATA space is the address range for the MPU XRAM (0x0000 to 0x3FF). All MPU data words are in 4-byte (32-bit) format. Typing ]A? will access the 32-bit word located at the byte address 4 * A = 0x28. The energy accumulation registers of the Demo Code can be accessed by typing two Dollar signs (“$$”), typing question marks will display negative decimal values if the most significant bit is set. RAM access is limited to the lower 1KB address range. Read and write operations will “wrap around” at higher addresses, i.e. )200? will yield the same result as )0? Commands for DIO RAM (Configuration RAM) and SFR Control: R DIO AND SFR CONTROL Description: Allows the user to read from and write to DIO RAM and special function registers (SFRs). Usage: R [option] [register] … [option] Command combinations: RIx… Example: Select I/O RAM location x (0x2000 offset is automatically added) Rx… Select internal SFR at address x Ra???... Read consecutive SFR registers in Decimal, starting at address a Ra$$$... Read consecutive registers in Hex, starting at address a Ra=n=m… Set values of consecutive registers to n and m starting at address a RI2$$$ Read DIO RAM registers 2, 3, and 4 in Hex. DIO or Configuration RAM space is the address range 0x2000 to 0x20FF. This RAM contains registers used for configuring basic hardware and functional properties of the 71M6513/6513H and is organized in bytes (8 bits). The 0x2000 offset is automatically added when the command RI is typed. The SFRs (special function registers) are located in internal RAM of the 80515 core, starting at address 0x80. Page: 19 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for EEPROM Control: EE EEPROM CONTROL Description: Allows user to enable read and write to EEPROM. Usage: EE [option] [arguments] Command combinations: EECn EEPROM Access (1 Æ Enable, 0 Æ Disable) EERa.b Read EEPROM at address 'a' for 'b' bytes. EESabc..xyz Write characters to buffer (sets Write length) EETa Transmit buffer to EEPROM at address 'a'. EEWa.b...z Write values to buffer EEShello EET$0210 Writes 'hello' to buffer, then transmits buffer to EEPROM starting at address 0x210. Example: Due to buffer size restrictions, the maximum number of bytes handled by the EEPROM command is 0x40. Auxiliary Commands: Typing a comma (“,”) repeats the command issued from the previous command line. This is very helpful when examining the value at a certain address over time, such as the CE DRAM address for the temperature (0x40). The slash (“/”) is useful to separate comments from commands when sending macro text files via the serial interface. All characters in a line after the slash are ignored. Commands controlling the CE, TMUX and the RTM: C COMPUTE ENGINE CONTROL Description: Allows the user to enable and configure the compute engine. Usage: C [option] [argument] Command combinations: CEn Compute Engine Enable (1 Æ Enable, 0 Æ Disable) CTn Select input n for TMUX output pin. n is interpreted as a decimal number. CREn RTM output control (1 Æ Enable, 0 Æ Disable) CRSa.b.c.d Selects CE addresses for RTM output CE0 Disables CE, followed by “CE OFF” display on LCD. The Demo Code will reset if the WD timer is enabled. CT3 Selects the VBIAS signal for the TMUX output pin Example: Page: 20 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands controlling the Auto-Calibration Function: CL AUTO-CALIBRATION CONTROL Description: Allows the user to initiate auto-calibration and to store calibration values. Usage: CL [option] Command combinations: CLB Begin auto-calibration. Prior to auto-calibration, the calibration coefficients are automatically restored from flash memory. If the coefficients are not unity gain (0x4000), auto-calibration will yield poor results. CLS Save calibration coefficients to EEPROM starting at address 0x0004 CLR Restore calibration coefficients from EEPROM CLD Restore coefficients from flash memory CLB Starts auto-calibration Example: Before starting the auto-calibration process, target values for voltage and current must be entered in I/O RAM prior to calibration (V at 0x2029, I at 0x202A, duration in accumulation intervals at 0x2028), and the target voltage and current must be applied constantly during calibration. No phase adjustment will be performed. Coefficients can be saved to EEPROM using the CLS command. Commands controlling the Pulse Counter Function (Demo Code Revision 3.05 only) CP PULSE-COUNT CONTROL Description: Allows the user to control the pulse count functions. Usage: CP [option] Command combinations: CPA Start pulse counting for time period defined with the CPD command. Pulse counts will display with commands M15.2, M16.2 CPC Clear the absolute pulse count displays (shown with commands M15.1, M16.1) CPDn Set time window for pulse counters to n seconds, n is interpreted as a decimal number. CPD60 Set time window to 60 seconds. Example: Pulse counts accumulated over a time window defined by the CPD command will be displayed by M15.2 or M16.2 after the defined time has expired. Commands M15.1 and M16.1 will display the absolute pulse count for the W and VAR outputs. These displays are reset to zero with the CPC command (or the XRAM write )1=2). Commands M15.2 and M16.2 will display the number of pulses counted during the interval defined by the CPD command. These displays are reset only after a new reading, as initiated by the CPA command. Page: 21 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for Identification and Information: I INFORMATION MESSAGES Description: Allows user to read and write information messages. Usage: I [option] [argument] Command combinations: I0 Displays complete version information I1 Displays Demo Code version string I1=abcdef Change Demo Code version string I2 Displays Copyright string I3 CE Version string I3=abcdef Change CE Code version string I1 Returns Demo Code version Example: The I commands are mainly used to identify the revisions of Demo Code and the contained CE code. P PROFILE OF METER Description: Returns current meter configuration profile Usage: P The profile of the meter is a summary of the important settings of the I/O RAM registers. Page: 22 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for Controlling the Metering Values Shown on the LCD Display: M METER DISPLAY CONTROL (LCD) Description: Allows user to select internal variables to be displayed. Usage: M [option]. [option] Command combinations: M Displays “HELLO” message M0 Disables display updates M1 Temperature (C° delta from nominal) M2 Frequency (Hz) M3. [phase] Wh Total Consumption (display wraps around at 999.999) M4. [phase] Wh Total Inverse Consumption (display wraps around at 999.999) M5. [phase] VARh Total Consumption (display wraps around at 999.999) Example: M6. [phase] VARh Total Inverse Consumption (display wraps around at 999.999) M7. [phase] VAh Total (display wraps around at 999.999) M8 Operating Time (in hours) M9 Real Time Clock M10 Calendar Date M11. [phase] V/I Angle at Phase (degrees) M13.1 Main edge count (accumulated) – zero transitions of the input signal M13.2 CE main edge count for the last accumulation interval M14.1 Absolute count for W pulses. Reset with CPC command. Demo Code revision 3.05 only. M14.2 Count for W pulses in time window defined by the CPD command. Demo Code revision 3.05 only. M15.1 Absolute count for VAR pulses. Reset with CPC command. Demo Code revision 3.05 only. M15.2 Count for W pulses in time window defined by the CPD command. Demo Code revision 3.05 only. M3.3 Displays Wh total consumption of phase C. M5.0 Displays VARh total consumption for all phases. Displays for total consumption wrap around at 999.999Wh (or VARh, VAh) due to the limited number of available display digits. Internal registers (counters) of the Demo Code are 64 bits wide and do not wrap around. When entering the phase parameter, use 1 for phase A, 2 for phase B, 3 for phase C, and 0 for all phases. Page: 23 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for Controlling the RMS Values Shown on the LCD Display: MR METER RMS DISPLAY CONTROL (LCD) Description: Allows user to select meter RMS display for voltage or current. Usage: MR [option]. [option] Command combinations: MR1. [phase] Displays instantaneous RMS current MR2. [phase] Displays instantaneous RMS voltage MR1.3 Displays phase C RMS current. Example: On the D6513T3C1 Demo Boards, phase 4 is the measured neutral current. No error message is issued when an invalid parameter is entered, e.g. MR1.8. Commands for Controlling the MPU Power Save Mode: PS POWER SAVE MODE Description: Enters power save mode Usage: PS Disables CE, ADC, CKOUT, ECK, RTM, SSI, TMUX VREF, and serial port, sets MPU clock to 38.4KHz. Return to normal mode is achieved by resetting the MPU (Z command). Commands for Controlling the RTC: RT REAL TIME CLOCK CONTROL Description: Allows the user to read and set the real time clock. Usage: RT [option] [value] … [value] Command combinations: RTDy.m.d.w: Day of week (year, month, day, weekday [1 = Sunday]) RTR Read Real Time Clock. RTTh.m.s Time of day: (hr, min, sec). RTAs.t Real Time Adjust: (start, trim). Allows trimming of the RTC. If s > 0, the speed of the clock will be adjusted by ‘t’ parts per billion (PPB). If the CE is on, the value entered with 't' will be changing with temperature, based on Y_CAL, Y_CALC and Y_CALC2. RTD05.03.17.5 Programs the RTC to Thursday, 3/17/2005 RTA1.+1234 Speeds up the RTC by 1234 PPB. Example: The “Military Time Format” is used for the RTC, i.e. 15:00 is 3:00 PM. Page: 24 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Commands for Accessing the Trim Control Registers: T TRIM CONTROL Description: Allows user to read trim and fuse values. Usage: T [option] Command combinations: T4 Read fuse 4 (TRIMM). T5 Read fuse 5 (TRIMBGA) T6 Read fuse 6 (TRIMBGB). T4 Reads the TRIMM fuse. Example: These commands are only accessible for the 71M6513H (0.1%) parts. When used on a 71M6513 (0.5%) part, the results will be displayed as zero. Reset Commands: W, Z RESET Description: Soft Reset and watchdog control Usage: W, Z Commands: W Halts the Demo Code program, thus suppressing the triggering of the hardware watchdog timer. This will cause a reset, if the watchdog timer is enabled. Demo Code revision 3.05 only. Z Soft reset. This command acts like a hardware reset. The energy accumulators in XRAM will retain their values. Page: 25 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.8.2 USING THE DEMO BOARD FOR ENERGY MEASUREMENTS The 71M6513/6513H Demo Board was designed for use with current transformers (CT). The Demo Board may immediately be used with current transformers having 2,000:1 winding ratio and is programmed for a Kh factor of 3.2 and (see Section 1.8.4 for adjusting the Demo Board for transformers with different turns ratio). Once, voltage is applied and load current is flowing, the red LED D5 will flash each time an energy sum of 3.2 Wh is collected. The LCD display will show the accumulated energy in Wh when set to display mode 3 (command >M3 via the serial interface). Similarly, the red LED D6 will flash each time an energy sum of 3.2 VARh is collected. The LCD display will show the accumulated energy in VARh when set to display mode 5 (command >M5 via the serial interface). 1.8.3 ADJUSTING THE KH FACTOR FOR THE DEMO BOARD The 71M6513/6513H Demo Board is shipped with a pre-programmed scaling factor Kh of 3.2, i.e. 3.2Wh per pulse. In order to be used with a calibrated load or a meter calibration system, the board should be connected to the AC power source using the spade terminals on the bottom of the board. The current transformers should be connected to the dual-pin headers on the bottom of the board. The Kh value can be derived by reading the values for IMAX and VMAX (i.e. the RMS current and voltage values that correspond to the 250mV maximum input signal to the IC), and inserting them in the following equation for Kh: Kh = IMAX * VMAX * 66.1782 / (In_8 * WRATE * NACC * X) = 3.19902 Wh/pulse. The small deviation between the adjusted Kh of 3.19902 and the ideal Kh of 3.2 is covered by calibration. The default values used for the 71M6513/6513H Demo Board are: WRATE: IMAX: VMAX: In_8: NACC: X: 683 208 600 1 2520 1.5 (controlled by IA_SHUNT = -15) Explanation of factors used in the Kh calculation: WRATE: The factor input by the user to determine Kh IMAX: The current input scaling factor, i.e. the input current generating 177mVrms at the IA/IB/IC input pins of the 71M6513. 177mV rms is equivalent to 250mV peak. VMAX: The voltage input scaling factor, i.e. the voltage generating 177mVrms at the VA/VB/VC input pins of the 71M6513 In_8: The setting for the additional ADC gain (8 or 1) determined by the CE register IA_SHUNT NACC: The number of samples per accumulation interval, i.e. PRE_SAMPS *SUM_CYCLES X: The pulse rate control factor determined by the CE registers PULSE_SLOW and PULSE_FAST Almost any desired Kh factor can be selected for the Demo Board by resolving the formula for WRATE: WRATE = (IMAX * VMAX * 66.1782) / (Kh * In_8 * NACC * X) For the Kh of 3.2Wh, the value 683 (decimal) should be entered for WRATE at location 2D (using the CLI command >]2D=+683). Page: 26 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.8.4 ADJUSTING THE DEMO BOARDS TO DIFFERENT CURRENT TRANSFORMERS The Demo Board is prepared for use with 2000:1 current transformers (CTs). This means that for the unmodified Demo Board, 208A on the primary side at 2000:1 ratio result in 104mA on the secondary side, causing 177mV at the 1.7Ω resistor pairs R24/R25, R36/R37, R56/R57 (2 x 3.4Ω in parallel). In general, when IMAX is applied to the primary side of the CT, the voltage Vin at the IA, IB, or IC input of the 71M6513 IC is determined by the following formula: Vin = R * I = R * IMAX/N where N = transformer winding ratio, R = resistor on the secondary side If, for example, IMAX = 208A are applied to a CT with a 2500:1 ratio, only 83.2mA will be generated on the secondary side, causing only 141mV. The steps required to adapt a 71M6513 Demo Board to a transformer with a winding ratio of 2500:1 are outlined below: 1) The formula Rx = 177mV/(IMAX/N) is applied to calculate the new resistor Rx. We calculate Rx to 2.115Ω 2) Changing the resistors R24/R25, R106/R107 to a combined resistance of 2.115Ω (for each pair) will cause the desired voltage drop of 177mV appearing at the IA, IB, or IC inputs of the 71M6513 IC. 3) WRATE should be adjusted to achieve the desired Kh factor, as described in 1.8.3. Simply scaling IMAX is not recommended, since peak voltages at the 71M6513 inputs should always be in the range of 0 through ±250mV (equivalent to 177mV rms). If a CT with a much lower winding ratio than 1:2,000 is used, higher secondary currents will result, causing excessive voltages at the 71M6513 inputs. Conversely, CTs with much higher ratio will tend to decrease the useable signal voltage range at the 71M6513 inputs and may thus decrease resolution. 1.8.5 ADJUSTING THE DEMO BOARDS TO DIFFERENT VOLTAGE DIVIDERS The 71M6513 Demo Board comes equipped with its own network of resistor dividers for voltage measurement mounted on the PCB. The resistor values (for the D6513T3B2 Demo Board) are 2.5477MΩ (R15-R21, R26-R31 combined) and 750Ω (R32), resulting in a ratio of 1:3,393.933. This means that VMAX equals 176.78mV*3,393.933 = 600V. A large value for VMAX has been selected in order to have headroom for overvoltages. This choice need not be of concern, since the ADC in the 71M6513 has enough resolution, even when operating at 120Vrms or 240Vrms. If a different set of voltage dividers or an external voltage transformer (potential transformer) is to be used, scaling techniques similar to those applied for the current transformer should be used. In the following example we assume that the line voltage is not applied to the resistor divider for VA formed by R15-R21, R26-R31, and R32, but to a voltage transformer with a ratio N of 20:1, followed by a simple resistor divider. We also assume that we want to maintain the value for VMAX at 600V to provide headroom for large voltage excursions. When applying VMAX at the primary side of the transformer, the secondary voltage Vs is: Vs = VMAX / N Vs is scaled by the resistor divider ratio RR. When the input voltage to the voltage channel of the 71M6513 is the desired 177mV, Vs is then given by: Vs = RR * 177mV Resolving for RR, we get: RR = (VMAX / N) / 177mV = (600V / 30) / 177mV = 170.45 This divider ratio can be implemented, for example, with a combination of one 16.95kΩ and one 100Ω resistor. Page: 27 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual If potential transformers (PTs) are used instead of resistor dividers, phase shifts will be introduced that will require negative phase angle compensation. TERIDIAN can supply Demo Code that accepts negative calibration factors for phase. 1.9 CALIBRATION PARAMETERS 1.9.1 GENERAL CALIBRATION PROCEDURE Any calibration method can be used with the 71M6513/6513H chips. This Demo Board User’s Manual presents calibration methods with three or five measurements as recommended methods, because they work with most manual calibration systems based on counting "pulses" (emitted by LEDs on the meter). Naturally, a meter in mass production will be equipped with special calibration code offering capabilities beyond those of the Demo Code. It is basically possible to calibrate using voltage and current readings, with or without pulses involved. For this purpose, the MPU Demo Code can be modified to display averaged voltage and current values (as opposed to momentary values). Also, automated calibration equipment can communicate with the Demo Boards via the serial interface and extract voltage and current readings. This is possible even with the unmodified Demo Code. A complete calibration procedure is given in section 0 of this manual. Regardless of the calibration procedure used, parameters (calibration constants) will result that will have to be applied to the 71M6513/6513H chip in order to make the chip apply the modified gains and phase shifts necessary for accurate operation. Table 1-4 shows the names of the calibration constants, their function, and their location in the CE RAM. Again, the command line interface can be used to store the calibration constants in their respective CE RAM addresses. For example, the command >]8=+16302 stores the decimal value 16302 in the CE RAM location controlling the gain of the current channel (CAL_IA) for phase A. The command >]9=4005 stores the hexadecimal value 0x4005 (decimal 16389) in the CE RAM location controlling the gain of the voltage channel for phase A (CAL_VA). Constant CE Address (hex) CAL_VA CAL_VB CAL_VC 0x09 0x0B 0x0D Adjusts the gain of the voltage channels. +16384 is the typical value. The gain is directly proportional to the CAL parameter. Allowed range is 0 to 32767. If the gain is 1% slow, CAL should be increased by 1%. CAL_IA CAL_IB CAL_IC 0x08 0x0A 0x0C Adjusts the gain of the current channels. +16384 is the typical value. The gain is directly proportional to the CAL parameter. Allowed range is 0 to 32767. If the gain is 1% slow, CAL should be increased by 1%. PHADJ_A PHADJ_B PHADJ_C 0x0E 0x0F 0x10 This constant controls the CT phase compensation. No compensation occurs when PHADJ=0. As PHADJ is increased, more compensation is introduced. TEMP_NOM 0x11 TEMP_RAW reading Description Table 1-4: CE RAM Locations for Calibration Constants Page: 28 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.9.2 CALIBRATION MACRO FILE The macro file in Figure 1-7 contains a sequence of the serial interface commands. It is a simple text file and can be created with Notepad or an equivalent ASCII editor program. The file is executed with HyperTerminal’s Transfer->Send Text File command. ]8=+16022/ ]9=+16381/ ]a=+16019/ ]b=+16370/ ]c=+15994/ ]d=+16376/ ]e=+115/ ]f=+113/ ]10=+109/ ce1 CAL_IA (gain=CAL_IA/16384) CAL_VA (gain=CAL_VA/16384) CAL_IB (gain=CAL_IB/16384) CAL_VB (gain=CAL_VB/16384) CAL_IC (gain=CAL_IC/16384) CAL_VC (gain=CAL_VC/16384) PHADJ_A (default 0) PHADJ_B (default 0) PHADJ_C (default 0) Figure 1-7: Typical Calibration Macro file It is possible to send the calibration macro file to the 71M6513/71M6513H for “temporary” calibration. This will temporarily change the CE data values. Upon power up, these values are refreshed back to the default values stored in flash memory. Thus, until the flash memory is updated, the macro file must be loaded each time the part is powered up. The macro file is run by first issuing the ce0 command to turn off the compute engine and then sending the file with the transfer Æ send text file procedure. Use the Transfer Æ Send Text File command! 1.9.3 UPDATING THE 6513_DEMO.HEX FILE The io_merge program updates the 6513_demo.hex file with the values contained in the macro file. This program is executed from a DOS command line window. Executing the io_merge program with no arguments will display the syntax description. To merge macro.txt and old_6513_demo.hex into new_6513_demo.hex, use the command: io_merge old_6513_demo.hex macro.txt new_6513_demo.hex The new hex file can be written to the 71M6513/71M6513H through the ICE port using the ADM51 in-circuit emulator. This step makes the calibration to the meter permanent. 1.9.4 UPDATING CALIBRATION DATA IN FLASH MEMORY WITHOUT USING THE ICE OR A PROGRAMMER It is possible to make data permanent that had been entered temporarily into the CE RAM. The transfer to flash memory is done using the following serial interface command: >]U Thus, after transferring calibration data with manual serial interface commands or with a macro file, all that has to be done is invoking the U command. Similarly, calibration data can also stored in EEPROM using the CLS command. After reset, calibration data is copied from the EEPROM, if present. Otherwise, calibration data is copied from the flash memory. Writing 0xFF into the first few bytes of the EEPROM deactivates any calibration data previously stored to the EEPROM. Page: 29 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.9.5 AUTOMATIC GAINS CALIBRATION Starting with Demo Code revision 3.04, it is possible to perform a simple automatic calibration. This calibration is performed for resistive loads only and will not correct phase angle. The steps required for the calibration are: 1. Enter operating values for voltage and current in I/O RAM. The voltage is entered at address 0x2029 (e.g. with the command )29=+2400 for 240V), the current is entered at 0x202A (e.g. with the command )2A=+300 for 30A) and the duration measured in accumulation intervals is entered at 0x2028. 2. The operating voltage and current defined in step 1 must be applied to the meter (Demo Board). 3. The CLB (Begin Calibration) command must be entered via the serial interface. The operating voltage and current must be maintained accurately while the calibration is being performed. 4. The calibration procedure will automatically reset CE addresses 08, 09, 0x0A, 0x0B, 0x0C, and 0x0D to nominal values (0x4000), and 0x0E, 0x0F and 0x10 to zero prior to starting the calibration. Automatic calibration also reads the chip temperature and enters it in CE location 0x11 for proper temperature compensation. 5. The LCD showing the “HELLO” message will signal completion of the automatic calibration. Enter M3 or another serial interface command to bring the display back to normal. 6. CE addresses 08, 09, 0x0A, 0x0B, 0x0C, and 0x0D will now show values other than 0x4000. These values can be stored in EEPROM by issuing the CLS command. Tip: Current transformers of a given type usually have very similar phase angle for identical operating conditions. If the phase angle is accurately determined for one current transformer, the corresponding phase adjustment coefficient PHADJ_X can be entered for all calibrated units. 1.9.6 LOADING THE 6513_DEMO.HEX FILE INTO THE DEMO BOARD Hardware Interface for Programming: The 71M6513/6513H IC provides an interface for loading code into the internal flash memory. This interface consists of the following signals: E_RXTX (data) E_TCLK (clock) E_RST (reset) These signals, along with V3P3 and GND are available on the emulator header J14. Production meters may be equipped with much simpler programming connectors, e.g. a 5x1 header. Programming of the flash memory requires a specific in-circuit emulator, the ADM51 by Signum Systems (http//www.signumsystems.com) or the Flash Programmer (TFP-1) provided by TERIDIAN Semiconductor. A gang programmer is available for high-volume production. In-Circuit Emulator: If firmware exists in the 71M6513/6513H flash memory, this memory has to be erased before loading a new file into memory. Figure 1-8 and Figure 1-9 show the emulator software active. In order to erase the flash memory, the RESET button of the emulator software has to be clicked followed by the ERASE button (Figure 1-8). Once the flash memory is erased, the new file can be loaded using the commands File followed by Load. The dialog box shown in Figure 1-9 will then appear making it possible to select the file to be loaded by clicking the Browse button. Once the file is selected, pressing the OK button will load the file into the flash memory of the 71M6513/6513H IC. At this point, the emulator probe (cable) can be removed. Once the 71M6513/6513H IC is reset using the reset button on the Demo Board, the new code starts executing. Flash Programmer Module (TFP-1): Follow the instructions given in the User Manual for the TFP-1. Page: 30 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Figure 1-8: Emulator Window Showing Reset and Erase Buttons (see Arrows) Figure 1-9: Emulator Window Showing Erased Flash Memory and File Load Menu Page: 31 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.9.7 THE PROGRAMMING INTERFACE OF THE 71M6513/6513H Flash Downloader/ICE Interface Signals The signals listed in Table 1-5 are necessary for communication between the Flash Downloader or ICE and the 71M6513/6513H. Signal Direction Function E_TCLK Output from 71M6513/6513H Data clock E_RXTX Bi-directional Data input/output E_RST Bi-directional Flash Downloader Reset (active low) Table 1-5: Flash Programming Interface Signals The other signals accessible at the emulator interface connector J14 (E_TBUS[0]-E_TBUS[3], E_ISYNC/BRKRQ) are used for the trace debugger, if available. The E_RST signal should only be driven by the Flash Downloader when enabling these interface signals. The Flash Downloader must release E_RST at all other times. Page: 32 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.10 DEMO CODE 1.10.1 DEMO CODE DESCRIPTION The Demo Board is shipped preloaded with Demo Code revision 3.0.4 or later in the 71M6513 or 71M6513H chip. The code revision can easily be verified by entering the command >i1 via the serial interface (see section 1.8.1). Check with your local TERIDIAN representative or FAE for the latest revision. Some Demo Boards are shipped with Demo Code 3.03. These boards can be updated to revision 3.04 or later using either an in-circuit emulator (ICE) or the Flash Programmer (TFP-1), as described in section 1.9.6. The Demo Code is useful due to the following features: • It provides basic metering functions such as pulse generation, display of accumulated energy, frequency, date/time, and enables the user to evaluate the parameters of the metering IC such as accuracy, harmonic performance, etc. • It maintains and provides access to basic household functions such as real-time clock (RTC). • It provides access to control and display functions via the serial interface, enabling the user to view and modify a variety of meter parameters such as Kh, calibration coefficients, temperature compensation etc. • It provides libraries for access of low-level IC functions to serve as building blocks for code development. A detailed description of the Demo Code can be found in the Software User’s Guide (SUG). In addition, the comments contained in the library provided with the Demo Kit can serve as useful documentation. The Software User’s Guide contains the following information: • Design guide • Design reference for routines • Tool Installation Guide • List of library functions • 80515 MPU Reference (hardware, instruction set, memory, registers) • Description of serial interface commands Page: 33 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 1.10.2 DEMO CODE MPU PARAMETERS In the Demo Code, certain MPU XRAM parameters have been given fixed addresses in order to permit easy external access. These variables can be read via the serial interface, as described in section 1.7.1, with the )n$ command and written with the )n=xx command where n is the word address. Note that accumulation variables are 64 bits long and are accessed with )n$$ (read) and )n=hh=ll (write) in the case of accumulation variables. Default values are the values assigned by the Demo Code on start-up. MPU INPUT PARAMETERS All MPU Input Parameters are loaded by the MPU at startup and should not need adjustment during meter calibration. MPU Input Parameters for Metering XRAM Word Address Default Value Name Description For each element, if WSUM_X or VARSUM_X of that element exceeds WCREEP_THR, the sample values for that element are not zeroed. Otherwise, the accumulators for Wh, VARh, and VAh are not updated and the instantaneous value of IRMS for that element is zeroed. 0x00 5917 WCREEP_THR LSB = 9.4045*10-13 VMAX IMAX Wh Demo Code revision 3.04: The default value is 1536. Demo Code revision 3.05: The default value 5917 is equivalent to 2.5Wh/h. Bit 0: 0x01 0 CONFIG Sets VA calculation mode. 0: VRMS*ARMS 1: W 2 + VAR 2 Bit 1: Clears accumulators for Wh, VARh, VAh. This bit need not be reset. Demo Code revision 3.04: Not implemented (default = 0) 0x02 136105056 PK_VTHR Demo Code revision 3.05: When the voltage exceeds this value, bit 5 in the MPU status word is set, and the MPU might choose to log a warning. Event logs are not implemented in Demo Code. LSB = 9.4045*10-13*VMAX2 V2hRMS The default value of 136105056 is equivalent to 407.3VRMS if VMAX = 600V and a 1-second accumulation interval is used. Demo Code revision 3.04: Not implemented (default = 0) 0x03 17695797 PK_ITHR Demo Code revision 3.05: When the current exceeds this value, bit 6 in the MPU status word is set, and the MPU might choose to log a warning. Event logs are not implemented in Demo Code. LSB = 9.4045*10-13*IMAX2 V2hRMS The default value of 17695797 is equivalent to 50.9ARMS if IMAX = 208A and a 1-second accumulation interval is used. Page: 34 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 0x09 6000 VMAX The nominal external RMS voltage that corresponds to 250mV peak at the ADC input. The meter uses this value to convert internal quantities to external. LSB=0.1V 0x0A 2080 IMAX The nominal external RMS current that corresponds to 250mv peak at the ADC input. The meter uses this value to convert internal quantities to external. LSB=0.1A Sample rate control for neutral current detection (D6513T3C1 Demo Boards only). The frequency of alternative multiplexer cycles (measuring V3 and temperature) is given by: f = 0x0F 10 ALT_MUX_RATE 2520.6 ALT _ MUX _ RATE The default setting results in a frequency of 252Hz. See section 1.10.4 for details. This address is only used by the “Neutral Current” Demo Code. For other Demo Code revisions, XRAM word address 0x0F is a reserved location. 0x13 44 ICREEP_THR For each element, if ISQSUM_X of that element exceeds ICREEP_THR, the sample values for that element are not zeroed. Otherwise, the accumulators for Wh, VARh, and VAh are not updated and the instantaneous value of IRMS for that element is zeroed. LSB = 9.4045*10-13 IMAX2 Wh Demo Code revision 3.05: The default value 44 is equivalent to 0.00644A2. Table 1-6: MPU Input Parameters for Metering MPU Input Parameters for Temperature Compensation XDATA Word Address Default Value Name 0x04 0 Y_CAL 0x05 0 Y_CALC 0x06 0 Y_CALC2 0x0B 0 PPMC PPM/C*26.84. Linear temperature compensation. A positive value will cause the meter to run faster when hot. This is applied to both V and I and will therefore have a double effect on products. Default is 0. PPM/C *1374. Square law compensation. A positive value will cause the meter to run faster when hot. This is applied to both V and I and will therefore have a double effect on products. Default is 0. Description Implement RTC trim. CORRECTION ( ppm ) = Y _ CAL Y _ CALC Y _ CALC 2 +T ⋅ +T2 ⋅ 10 100 1000 2 0x0C 0 PPMC2 0x0D 22721 DEGSCALE Scale factor for TEMP_X. TEMP_X=DEGSCALE*2-22*(TEMP_RAW_X-TEMP_NOM). Y_CAL, Y_CALC, Y_CALC2 are 16-bit signed integers, i.e. the range is –32,767 to +32,768 Table 1-7: MPU Input Parameters for Temperature Compensation Page: 35 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual MPU Input Parameters for Pulse Generation XDATA Word Address Default Value Name Description 0x07 0 PULSEW_SRC This address contains a number that points to the selected pulse source. Selectable pulse sources are listed in Table 1-9. 0x08 4 PULSER_SRC This address contains a number that points to the selected pulse source. Selectable pulse sources are listed in Table 1-9. Table 1-8: MPU Parameters for Pulse Source Selection Any of the values listed in Table 1-9 can be selected for as a source for PULSEW and PULSER. The designation “source_I” refers to values imported by the consumer, “source_E” refers to energy exported by the consumer (energy generation). Number Pulse Source Description Number Pulse Source 0 WSUM Default for PULSEW_SRC 18 VA2SUM 1 W0SUM 19 WSUM_I Sum of imported real energy 2 W1SUM 20 W0SUM_I Imported real energy on element A 3 W2SUM 21 W1SUM_I Imported real energy on element B 4 VARSUM 22 W2SUM_I Imported real energy on element C 5 VAR0SUM 23 VARSUM_I Sum of imported reactive energy 6 VAR1SUM 24 VAR0SUM_I Imported reactive energy on element A 7 VAR2SUM 25 VAR1SUM_I Imported reactive energy on element B 8 I0SQSUM 26 VAR1SUM_I Imported reactive energy on element C 9 I1SQSUM 27 WSUM_E Sum of exported real energy 10 I2SQSUM 28 W0SUM_E Exported real energy on element A 11 INSQSUM 29 W1SUM_E Exported real energy on element B 12 V0SQSUM 30 W2SUM_E Exported real energy on element C 13 V1SQSUM 31 VARSUM_E Sum of exported reactive energy 14 V2SQSUM 32 VAR0SUM_E Exported reactive energy on element A 15 VASUM 33 VAR1SUM_E Exported reactive energy on element B 16 VA0SUM 34 VAR2SUM_E Exported reactive energy on element C 17 VA1SUM Default for PULSER_SRC Description Table 1-9: Selectable Pulse Sources Page: 36 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual MPU INSTANTANEOUS OUTPUT VARIABLES The Demo Code processes CE outputs after each accumulation interval. It calculates instantaneous values such as VRMS, IRMS, W and VA as well as accumulated values such as Wh, VARh, and VAh. Table 1-10 lists the calculated instantaneous values. XRAM Word Address Name 0x14 0x15 0x16 Vrms_A Vrms_B* Vrms_C* 0x17 0x18 0x19 Irms_A Irms_B Irms_C* 0x1A 0x1B 0x1C IPhase_A IPhase_B* IPhase_C* DESCRIPTION Vrms from element 0, 1, 2. LSB = 4.4575 ⋅ 10 −8 VMAX Nacc Irms from element 0, 1, 2. LSB = 4.4575 ⋅ 10 −8 IMAX In8 Nacc In-Vn phase from element n. The number of degrees In lags Vn. LSB=0.001°. Range = -180 to +180. Frequency of voltage selected by CE input. If the selected voltage is below the sag threshold, Frequency=0. 0x1D Frequency LSB 0x1E Delta_T 0x1F 0x20 VPhase_AB* VPhase_BC* ≡ FS ≈ 0.587 ⋅ 10 − 6 Hz 32 2 Deviation from Calibration temperature. LSB = 0.1 0C. Amount phase B lags phase A and amount phase B lags phase C. LSB=1° (0,360). If Vrms_A)1=2 Description Clears the accumulators for Wh, VARh, and VAh by setting bit 1 of the CONFIG register. >)A=+2080 Applies the value 208A to the IMAX register >)9=+6000 Applies the value 600V to the VMAX register >)22? Displays the operating time since the last power up (in 1/100 of hours) >)2F$$ Displays the total accumulated imported Wh energy (two $$ used for full 64 bit hex display) >MR2.1 Displays the current RMS voltage in phase A >MR1.2 Displays the current RMS current in phase B >RI5=26 Disables the emulator clock by setting bit 5 in I/O RAM address 0x05. >RI5=6 Re-enables the emulator clock by clearing bit 5 in I/O RAM address 0x05. >RI1C=1 Increments the RTC clock by one second. ]U Stores the current CE RAM variables in flash memory. The stored variables will be applied by the MPU at the next reset or power-up if no valid data is available from the EEPROM. >CLS Stores the current CE RAM variables in EEPROM memory. The stored variables will be applied by the MPU at the next reset or power-up. Table 1-13: CLI Commands for MPU Data Memory 1.10.4 DEMO CODE FOR NEUTRAL DETECTION (DEMO BOARD D6513T3C1) Normally a high neutral current indicates tampering, perhaps from a grounded or bypassed power conductor. The Neutral Current measurement is performed by acquiring the signal from a fourth current transformer that is connected to the auxiliary analog input, the V3 pin (pin 86). The analog data measured on this pin is referenced to the VBIAS pin (pin 81). The ICs supplied with the 71M6513/6513H Demo Kits may contain firmware versions with and without neutral current. On the CD-ROM containing the firmware sources and documentation, the files supporting neutral current code end with "NC". Neutral current is read using alternate multiplexer cycles, as controlled by the MUX_ALT bit in I/O RAM. While the TERIDIAN standard Demo Code revision 3.04 performs one alternate multiplexer cycle per second, the neutral current-capable Demo Code can perform alternate multiplexer cycles more frequently. When the alternate multiplexer cycle is triggered once every 10th CE_BUSY interrupt (i.e. every 3.97ms, or 252Hz), no interference with regular power measurement occurs, and the neutral current is still measured with an accuracy of about 1.5%. The sampling rate for the neutral current can be changed by changing the MPU (XDATA) address ALT_MUX_RATE, which is located at CE DRAM address 0x0F. The sample rate (2520.6), divided by the value entered into ALT_MUX_RATE controls the number of neutral current samples per second: f = 2520.6 ALT _ MUX _ RATE When the value of ALT_MUX_RATE decreased, the sample rate for the neutral current increases. The Minimum value for ALT_MUX_RATE is 10, i.e. 252Hz is the maximum recommended sample rate for neutral current. On Demo Code without neutral current, MPU XDATA address 0x0F accesses a reserved (and unused) memory location. Page: 40 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual The neutral current is available for display. The help text for the MR command describes how to display neutral current on the display. For the "M" command of the CLI for current, phase 4 signifies the neutral current. The accuracy data collected for several ALT_MUX_RATE settings is given in Table 1-14: Test Number Applied Current 1 2 3 4 5 6 7 8 9 10 11 200 150 100 50 25 10 5 2.5 1 0.5 0.25 ALT_MUX_RATE = 10 ALT_MUX_RATE = 25 ALT_MUX_RATE = 50 (100Hz) (51Hz) (252Hz) measured measured measured current error [%] current error [%] current error [%] 200.66 0.33 201.15 0.575 202.335 1.168 150.63 0.42 150.778 0.519 150.824 0.549 99.82 -0.18 99.765 -0.235 100.221 0.221 49.859 -0.282 49.76 -0.48 49.333 -1.334 24.889 -0.444 24.861 -0.556 24.951 -0.196 10.042 0.42 10.134 1.34 10.193 1.93 4.988 -0.24 5.132 2.64 5.155 3.1 2.486 -0.56 2.459 -1.64 2.535 1.4 1.036 3.6 1.067 6.7 1.071 7.1 0.564 12.8 0.581 16.2 0.592 18.4 0.324 29.6 0.328 31.2 0.334 33.6 Table 1-14: Neutral Current Accuracy at Various Sampling Frequencies MPU (XDATA) address 0x027 represents the neutral current (RMS value). For the standard Demo Code (revision 3.04), this address is a reserved location. In the CE interface, the CE address 0x56 represents the 32-bit neutral current value, I3SQSUM. It has different units than the current registers derived from the regular inputs IA, IB, and IC, because it is sampled at a different rate (default = 1/10) than the other current channels, and because the reference is not VREF, but VBIAS. If one accumulates data for 250 samples (with XDATA address 0x0F=10) the accumulated data is transferred to the MPU as one register on each XFER_BUSY interrupt. The values in between samples are equivalent to the previous acquired sample value. The actual LSB value for the neutral current measurement is computed from the following formula LSB NC = IMAX 2 431 ⋅ 10 3 ⋅ N ACC ⋅ A 2 h where: IMAX is the numerical value of the current corresponding to 176mV RMS at the IC input, NACC is the product of SUM_CYCLES and PRE_SAMPS, With IMAX = 208A and NACC = 2520, LSBNC becomes 39.8*10-6/A2h. Page: 41 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Page: 42 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2 2 APPLICATION INFORMATION 2.1 CALIBRATION THEORY A typical meter has phase and gain errors as shown by φS, AXI, and AXV in Figure 2-1. Following the typical meter convention of current phase being in the lag direction, the small amount of phase lead in a typical current sensor is represented as -φS. The errors shown in Figure 2-1 represent the sum of all gain and phase errors. They include errors in voltage attenuators, current sensors, and in ADC gains. In other words, no errors are made in the ‘input’ or ‘meter’ boxes. INPUT I φL φ L is phase lag ERRORS −φS METER IRMS A XI Π V IDEAL = I , φS is phase lead W V RMS AXV ERROR ≡ ACTUAL = I AXI IDEAL = IV cos(φ L ) ACTUAL = IV AXI AXV cos(φ L − φ S ) IDEAL = V , ACTUAL = V AXV ACTUAL − IDEAL = ACTUAL − 1 IDEAL IDEAL Figure 2-1: Watt Meter with Gain and Phase Errors. During the calibration phase, we measure errors and then introduce correction factors to nullify their effect. With three unknowns to determine, we must make at least three measurements. If we make more measurements, we can average the results. 2.1.1 CALIBRATION WITH THREE MEASUREMENTS The simplest calibration method is to make three measurements. Typically, a voltage measurement and two Watt-hour (Wh) measurements are made. A voltage display can be obtained for test purposes via the command >MR2.1 in the serial interface. Let’s say the voltage measurement has the error EV and the two Wh measurements have errors E0 and E60, where E0 is measured with φL = 0 and E60 is measured with φL = 60. These values should be simple ratios—not percentage values. They should be zero when the meter is accurate and negative when the meter runs slow. The fundamental frequency is f0. T is equal to 1/fS, where fS is the sample frequency (2560.62Hz). Set all calibration factors to nominal: CAL_IA = 16384, CAL_VA = 16384, PHADJA = 0. Page: 43 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual From the voltage measurement, we determine that 1.Î AXV = EV + 1 We use the other two measurements to determine φS and AXI. IV AXV AXI cos(0 − φ S ) − 1 = AXV AXI cos(φ S ) − 1 IV cos(0) 2. E0 = 2a. AXV AXI = 3. E 60 = IV AXV AXI cos(60 − φ S ) cos(60 − φ S ) − 1 = AXV AXI −1 IV cos(60) cos(60) 3a. E 60 = AXV AXI [cos(60) cos(φ S ) + sin(60) sin(φ S )] −1 cos(60) E0 + 1 cos(φ S ) = AXV AXI cos(φ S ) + AXV AXI tan(60) sin(φ S ) − 1 Combining 2a and 3a: 4. E 60 = E 0 + ( E 0 + 1) tan(60) tan(φ S ) 5. tan(φ S ) = 6.Î φ S = tan −1  E 60 − E 0 ( E 0 + 1) tan(60)  E 60 − E 0  ( E 1 ) tan( 60 ) +   0  and from 2a: 7.Î AXI = E0 + 1 AXV cos(φ S ) Now that we know the AXV, AXI, and φS errors, we calculate the new calibration voltage gain coefficient from the previous ones: CAL _ V NEW = CAL _ V AXV We calculate PHADJ from φS, the desired phase lag: [ ]   tan(φ S ) 1 + (1 − 2 −9 ) 2 − 2(1 − 2 −9 ) cos(2πf 0T ) PHADJ = 2 20   −9 −9  (1 − 2 ) sin( 2πf 0T ) − tan(φ S ) 1 − (1 − 2 ) cos(2πf 0T )  Page: 44 of 112 [ © 2005-2006 TERIDIAN Semiconductor Corporation ] Revision 5.6 71M6513/71M6513H Demo Board User’s Manual And we calculate the new calibration current gain coefficient, including compensation for a slight gain increase in the phase calibration circuit. CAL _ I AXI CAL _ I NEW = 1 1+ 2 − 20 PHADJ (2 + 2 PHADJ − 2(1 − 2 −9 ) cos(2πf 0T )) 1 − 2(1 − 2 −9 ) cos(2πf 0T ) + (1 − 2 −9 ) 2 − 20 2.1.2 CALIBRATION WITH FIVE MEASUREMENTS The five measurement method provides more orthogonality between the gain and phase error derivations. This method involves measuring EV, E0, E180, E60, and E300. Again, set all calibration factors to nominal, i.e. CAL_IA = 16384, CAL_VA = 16384, PHADJA = 0. First, calculate AXV from EV: 1.Î AXV = EV + 1 Calculate AXI from E0 and E180: IV AXV AXI cos(0 − φ S ) − 1 = AXV AXI cos(φ S ) − 1 IV cos(0) 2. E0 = 3. E180 = 4. E 0 + E180 = 2 AXV AXI cos(φ S ) − 2 5. AXV AXI = 6.Î AXI = IV AXV AXI cos(180 − φ S ) − 1 = AXV AXI cos(φ S ) − 1 IV cos(180) E 0 + E180 + 2 2 cos(φ S ) ( E 0 + E180 ) 2 + 1 AXV cos(φ S ) Use above results along with E60 and E300 to calculate φS. 7. E 60 = IV AXV AXI cos(60 − φ S ) −1 IV cos(60) = AXV AXI cos(φ S ) + AXV AXI tan(60) sin(φ S ) − 1 8. E300 = IV AXV AXI cos(−60 − φ S ) −1 IV cos(−60) = AXV AXI cos(φ S ) − AXV AXI tan(60) sin(φ S ) − 1 Subtract 8 from 7 9. E 60 − E300 = 2 AXV AXI tan(60) sin(φ S ) use equation 5: Page: 45 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual E 0 + E180 + 2 tan(60) sin(φ S ) cos(φ S ) 10. E 60 − E300 = 11. E 60 − E300 = ( E 0 + E180 + 2) tan(60) tan(φ S ) 12.Î φ S = tan −1   ( E 60 − E300 )   tan(60)( E 0 + E180 + 2)   Now that we know the AXV, AXI, and φS errors, we calculate the new calibration voltage gain coefficient from the previous ones: CAL _ V NEW = CAL _ V AXV We calculate PHADJ from φS, the desired phase lag: [ ]   tan(φ S ) 1 + (1 − 2 −9 ) 2 − 2(1 − 2 −9 ) cos(2πf 0T ) PHADJ = 2 20   −9 −9  (1 − 2 ) sin( 2πf 0T ) − tan(φ S ) 1 − (1 − 2 ) cos(2πf 0T )  [ ] And we calculate the new calibration current gain coefficient, including compensation for a slight gain increase in the phase calibration circuit. CAL _ I NEW = CAL _ I AXI 1 1+ 2 − 20 PHADJ (2 + 2 − 20 PHADJ − 2(1 − 2 −9 ) cos(2πf 0T )) 1 − 2(1 − 2 −9 ) cos(2πf 0T ) + (1 − 2 −9 ) 2 2.2 CALIBRATION PROCEDURES Calibration requires that a calibration system is used, i.e. equipment that applies accurate voltage, load current and load angle to the unit being calibrated, while measuring the response from the unit being calibrated in a repeatable way. By repeatable we mean that the calibration system is synchronized to the meter being calibrated. Best results are achieved when the first pulse from the meter opens the measurement window of the calibration system. This mode of operation is opposed to a calibrator that opens the measurement window at random time and that therefore may or may not catch certain pulses emitted by the meter. It is essential for a valid meter calibration to have the voltage stabilized a few seconds before the current is applied. This enables the Demo Code to initialize the 71M6513/6513H and to stabilize the PLLs and filters in the CE. This method of operation is consistent with meter applications in the field as well as with metering standards. Each meter phase must be calibrated individually. The procedures below show how to calibrate a meter phase with either three or five measurements. The PHADJ equations apply only when a current transformer is used for the phase in question. Note that positive load angles correspond to lagging current (see Figure 2-2). During calibration of any phase, a stable mains voltage has to be present on phase A. This enables the CE processing mechanism of the 71M6513/6513H necessary to obtain a stable calibration. Page: 46 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Voltage Positive direction Current lags voltage (inductive) +60° Current -60° Current leads voltage (capacitive) Voltage Generating Energy Using Energy Figure 2-2: Phase Angle Definitions The calibration procedures described below should be followed after interfacing the voltage and current sensors to the 71M6513/6513H chip. When properly interfaced, the V3P3 power supply is connected to the meter neutral and is the DC reference for each input. Each voltage and current waveform, as seen by the 71M6513/6513H, is scaled to be less than 250mV (peak). 2.2.1 CALIBRATION PROCEDURE WITH THREE MEASUREMENTS The calibration procedure is as follows: 1) All calibration factors are reset to their default values, i.e. CAL_IA = CAL_VA = 16384, and PHADJ_A = 0. 2) An RMS voltage Videal consistent with the meter’s nominal voltage is applied, and the RMS reading Vactual of the meter is recorded. The voltage reading error Axv is determined as Axv = (Vactual - Videal ) / Videal 3) Apply the nominal load current at phase angles 0° and 60°, measure the Wh energy and record the errors E0 AND E60. 4) Calculate the new calibration factors CAL_IA, CAL_VA, and PHADJ_A, using the formulae presented in section 2.1.1 or using the spreadsheet presented in section 2.2.4. 5) Apply the new calibration factors CAL_IA, CAL_VA, and PHADJ_A to the meter. The memory locations for these factors are given in section 1.9.1. 6) Test the meter at nominal current and, if desired, at lower and higher currents and various phase angles to confirm the desired accuracy. 7) Store the new calibration factors CAL_IA, CAL_VA, and PHADJ_A in the flash memory of the meter. If the calibration is performed on a TERIDIAN Demo Board, the methods shown in sections 1.9.3 and 1.9.4 can be used. 8) Repeat the steps 1 through 7 for each phase. 9) For added temperature compensation, read the value in CE RAM location 0x54 and write it to CE RAM location 0x11. If Demo Code 3.05 or later is used, this will automatically calculate the correction coefficients PPMC and PPMC2 from the nominal temperature entered in CE location 0x11 and from the characterization data contained in the on-chip fuses. Tip: Step 2 and the energy measurement at 0° of step 3 can be combined into one step. Page: 47 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.2.2 CALIBRATION PROCEDURE WITH FIVE MEASUREMENTS The calibration procedure is as follows: 1) All calibration factors are reset to their default values, i.e. CAL_IA = CAL_VA = 16384, and PHADJ_A = 0. 2) An RMS voltage Videal consistent with the meter’s nominal voltage is applied, and the RMS reading Vactual of the meter is recorded. The voltage reading error Axv is determined as Axv = (Vactual - Videal ) / Videal 3) Apply the nominal load current at phase angles 0°, 60°, 180° and –60° (-300°). Measure the Wh energy each time and record the errors E0, E60, E180, and E300. 4) Calculate the new calibration factors CAL_IA, CAL_VA, and PHADJ_A, using the formulae presented in section 2.1.2 or using the spreadsheet presented in section 2.2.4. 5) Apply the new calibration factors CAL_IA, CAL_VA, and PHADJ_A to the meter. The memory locations for these factors are given in section 1.9.1. 6) Test the meter at nominal current and, if desired, at lower and higher currents and various phase angles to confirm the desired accuracy. 7) Store the new calibration factors CAL_IA, CAL_VA, and PHADJ_A in the flash memory of the meter. If a Demo Board is calibrated, the methods shown in sections 1.9.3 and 1.9.4 can be used. 8) Repeat the steps 1 through 7 for each phase. 9) For added temperature compensation, read the value in CE RAM location 0x54 and write it to CE RAM location 0x11. If Demo Code 3.05 or later is used, this will automatically calculate the correction coefficients PPMC and PPMC2 from the nominal temperature entered in CE location 0x11 and from the characterization data contained in the on-chip fuses. Tip: Step 2 and the energy measurement at 0° of step 3 can be combined into one step. 2.2.3 CALIBRATION PROCEDURE FOR ROGOWSKI COIL SENSORS Demo Code containing CE code that is compatible with Rogowski coils is available from TERIDIAN Semiconductor. Rogowski coils generate a signal that is the derivative of the current. The CE code implemented in the Rogowski CE image digitally compensates for this effect and has the usual gain and phase calibration adjustments. Additionally, calibration adjustments are provided to eliminate voltage coupling from the sensor input. Current sensors built from Rogowski coils have a relatively high output impedance that is susceptible to capacitive coupling from the large voltages present in the meter. The most dominant coupling is usually capacitance between the primary of the coil and the coil’s output. This coupling adds a component proportional to the derivative of voltage to the sensor output. This effect is compensated by the voltage coupling calibration coefficients. As with the CT procedure, the calibration procedure for Rogowski sensors uses the meter’s display to calibrate the voltage path and the pulse outputs to perform the remaining energy calibrations. The calibration procedure must be done to each phase separately, making sure that the pulse generator is driven by the accumulated real energy for just that phase. In other words, the pulse generator input should be set to WhA, WhB, or WhC, depending on the phase being calibrated. In preparation of the calibration, all calibration parameters are set to their default values. VMAX and IMAX are set to reflect the system design parameters. WRATE and PUSE_SLOW, PULSE_FAST are adjusted to obtain the desired Kh. Page: 48 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Step 1: Basic Calibration: After making sure VFEED_A, VFEED_B, and VFEED_C are zero, perform either the three measurement procedure (2.2.1) or the five measurement calibration procedure (2.2.2) described in the CT section. Perform the procedure at a current large enough that energy readings are immune from voltage coupling effects. The one exception to the CT procedure is the equation for PHADJ—after the phase error, φs, has been calculated, use the PHADJ equation shown below. Note that the default value of PHADJ is not zero, but rather – 3973. PHADJ = PHADJ PREVIOUS − φ S 1786 50 f0 If voltage coupling at low currents is introducing unacceptable errors, perform step 2 below to select non-zero values for VFEED_A, VFEED_B, and VFEED_C. Step 2: Voltage Cancellation: Select a small current, IRMS, where voltage coupling introduces at least 1.5% energy error. At this current, measure the errors E0 and E180 to determine the coefficient VFEED . VFEED = E 0 − E180 25 I RMS VMAX − VFEEDPREVIOUS 2 2 I MAX VRMS 2.2.4 CALIBRATION SPREADSHEETS Calibration spreadsheets are available from TERIDIAN Semiconductor. They are also included in the CD-ROM shipped with any Demo Kit. Figure 2-3 shows the spreadsheet for three measurements. Figure 2-4 shows the spreadsheet for five measurements with three phases. For CT and shunt calibration, data should be entered into the calibration spreadsheets as follows: 1. Calibration is performed one phase at a time. 2. Results from measurements are generally entered in the yellow fields. Intermediate results and calibration factors will show in the green fields. 3. The line frequency used (50 or 60Hz0 is entered in the yellow field labeled AC frequency. 4. After the voltage measurement, measured (observed) and expected (actually applied) voltages are entered in the yellow fields labeled “Expected Voltage” and “Measured Voltage”. The error for the voltage measurement will then show in the green field above the two voltage entries. 5. The relative error from the energy measurements at 0° and 60° are entered in the yellow fields labeled “Energy reading at 0°” and “Energy reading at 60°”. The corresponding error, expressed as a fraction will then show in the two green fields to the right of the energy reading fields. 6. The spreadsheet will calculate the calibration factors CAL_IA, CAL_VA, and PHADJ_A from the information entered so far and display them in the green fields in the column underneath the label “new”. 7. If the calibration was performed on a meter with non-default calibration factors, these factors can be entered in the yellow fields in the column underneath the label “old”. For a meter with default calibration factors, the entries in the column underneath “old” should be at the default value (16384). Page: 49 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual A spreadsheet is also available for Rogowski coil calibration (see Figure 2-5). Data entry is as follows: Page: 50 of 112 1. All nominal values are entered in the fields of step one. 2. The applied voltage is entered in the yellow field labeled “Input Voltage Applied” of step 2. The entered value will automatically show in the green fields of the two other channels. 3. After measuring the voltages displayed by the meter, these are entered in the yellow fields labeled “Measured Voltage”. The spreadsheet will show the calculated calibration factors for voltage in the green fields labeled “CAL_Vx”. 4. The default values (-3973) for PHADJ_x are entered in the yellow fields of step 3. If the calibration factors for the current are not at default, their values are entered in the fields labeled “Old CAL_Ix”. 5. The errors of the energy measurements at 0°, 60°, -60°, and 180° are entered in the yellow fields labeled “% Error …”. The spreadsheet will then display phase error, the current calibration factor and the PHADJ_x factor in the green fields, one for each phase. 6. If a crosstalk measurement is necessary, it should be performed at a low current, where the effects of crosstalk are noticeable. First, if (old) values for VFEEDx exist in the meter, they are entered in the spreadsheet in the row labeled “Old VFEEDx”, one for each phase. If these factors are zero, “0” is entered for each phase. 7. Test current and test voltage are entered in the yellow fields labeled VRMS and IRMS. 8. The crosstalk measurement is now conducted at a low current with phase angles of 0° and 180°, and the percentage errors are entered in the yellow fields labeled “% error, 0 deg” and “% error, 180 deg”, one pair of values for each phase. The resulting VFEEDx factors are then displayed in the green fields labeled VFEEDx. © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 71M6511/71M6513/71M6515 Calibration Worksheet Three Measurements REV Date: Enter values in yellow fields Results will show in green fields… AC frequency: 50 4.2 10/25/2005 WJH Author: [Hz] (click on yellow field to select from pull-down list) PHASE A Energy reading at 0° Energy reading at +60° Voltage error at 0° % 0 0 0 Expected voltage Measured voltage 240 240 PHASE B Energy reading at 0° Energy reading at +60° Voltage error at 0° % 10 10 10 Expected voltage Measured voltage 240 264 PHASE C Energy reading at 0° Energy reading at +60° Voltage error at 0° % -3.8 -9 -3.8 Expected voltage Measured voltage 240 230.88 fraction 0 0 0 CAL_IA CAL_VA PHADJ_A old new 16384 16384 16384 16384 0 Voltage [V] [V] fraction 0.1 0.1 0.1 old CAL_IB CAL_VB PHADJ_B 16384 16384 CAL_IC CAL_VC PHADJ_C 16384 16384 Current lags voltage (inductive) Positive direction new 16384 14895 0 +60° -60° Current leads voltage (capacitive) [V] [V] fraction -0.038 -0.09 -0.038 old Current new 16409 17031 -5597 Voltage Generating Energy Using Energy Readings: Enter 0 if the error is 0%, [V] [V] enter -3 if meter runs 3% slow. Figure 2-3: Calibration Spreadsheet for Three Measurements 71M6511/71M6513/71M6515 Calibration Worksheet Five Measurements PI Results will show in green fields… Enter values in yellow fields! REV Date: 0.019836389 Ts AC frequency: 50 Author: [Hz] 4.2 10/25/2005 WJH (click on yellow field to select from pull-down list) PHASE A Energy reading at 0° Energy reading at +60° Energy reading at -60° Energy reading at 180° Voltage error at 0° % 2 2.5 1.5 2 1 fraction 0.02 0.025 0.015 0.02 0.01 Expected voltage [V] 240 242.4 % 2 2 2 2 1 fraction 0.02 0.02 0.02 0.02 0.01 240 242.4 % 0 0 0 0 0 fraction 0 0 0 0 0 240 240 PHASE B Energy reading at 0° Energy reading at +60° Energy reading at -60° Energy reading at 180° Voltage error at 0° Expected voltage [V] PHASE C Energy reading at 0° Energy reading at +60° Energy reading at -60° Energy reading at 180° Voltage error at 0° Expected voltage [V] CAL_IA CAL_VA PHADJ_A old new 16384 16384 16220 16222 371 Voltage Positive direction Measured voltage [V] CAL_IB CAL_VB PHADJ_B old new 16384 16384 16223 16222 0 +60° Current -60° Current leads voltage (capacitive) Voltage Measured voltage [V] CAL_IC CAL_VC PHADJ_C Current lags voltage (inductive) old new 16384 16384 16384 16384 0 Generating Energy Using Energy Readings: Enter 0 if the error is 0%, enter +5 if meter runs 5% fast, enter -3 if meter runs 3% slow. Measured voltage [V] Figure 2-4: Calibration Spreadsheet for Five Measurements Page: 51 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual Calibration Procedure for Rogowski Coils Enter values in yellow fields! Results will show in green fields… Step 1: Enter Nominal Values: Nominal CAL_V Nominal CAL_I PHADJ WRATE VMAX Calibration Frequency [Hz] IMAX (incl. ISHUNT) PULSE_FAST PULSE_SLOW NACC 16384 16384 -3973 179 600 50 30.000 -1 -1 2520 Step 2: VRMS Calibration: Enter old CAL_VA Input Voltage Applied Measured Voltage CAL_Vx Resulting Nominal Values: X 6 Kh (Wh) 0.440 REV Date: Author: 4.3 11/18/2005 WJH Angle Sensitivity (deg/LSB) 50Hz 1 1 1 -1 5.60E-04 50 60 32768 -32768 Phase A Phase B Phase C 16384 16384 16384 240 240 240 235.612 236.55 234.72 16689 16623 16753 Deg/ct 5.60E-04 Step 3: Current Gain and Phase Calibration Phase A Phase B Phase C old PHADJ -3973 -3973 -3973 Old CAL_Ix 16384 16384 16384 %Error, 60° -3.712 -3.912 -5.169 %Error, -60° -3.381 -2.915 -4.241 %Error, 0° -3.591 -3.482 -4.751 %Error, 180° -3.72 -3.56 -4.831 Phase Error (°) 0.0547319 0.1647659 0.1533716 PHADJ -4070.74 -4267.22 -4246.88 CAL_Ix 17005.641 16981.934 17208.457 Step 4: Crosstalk Calibration (Equalize Gain for 0° and 180°) VRMS 240 Phase A Phase B IRMS 0.30 Old VFEEDx 0 0 % Error, 0deg 1.542 1.61 %Error, 180deg -1.634 -1.743 VFEEDx -13321 -14064 Phase C 0 1.706 -1.884 -15058 1. Rogowski coils have significant crosstalk from voltage to current. This contributes to gain and phase errors. 2. Therefore, before calibrating a Rogowski meter, a quick 0° load line should be run to determine at what current the crosstalk contributes at least 1% error. 3. Crosstalk calibration should be performed at this current or lower. 4. If crosstalk contributes an E0 error at current Ix, there will be a 0.1% error in E60 at 15*Ix. Figure 2-5: Calibration Spreadsheet for Rogowski coil Page: 52 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.2.5 COMPENSATING FOR NON-LINEARITIES Nonlinearity is most noticeable at low currents, as shown in Figure 2-6, and can result from input noise and truncation. Nonlinearities can be eliminated using the QUANT variable. 12 error [%] 10 error 8 6 4 2 0 0.1 1 10 100 I [A] Figure 2-6: Non-Linearity Caused by Quantification Noise The error can be seen as the presence of a virtual constant noise current. While 10mA hardly contribute any error at currents of 10A and above, the noise becomes dominant at small currents. The value to be used for QUANT can be determined by the following formula: error V ⋅I 100 QUANT = − VMAX ⋅ IMAX ⋅ LSB Where error = observed error at a given voltage (V) and current (I), VMAX = voltage scaling factor, as described in section 1.8.3, IMAX = current scaling factor, as described in section 1.8.3, LSB = QUANT LSB value = 7.4162*10-10W Example: Assuming an observed error as in Figure 2-6, we determine the error at 1A to be +1%. If VMAX is 600V and IMAX = 208A, and if the measurement was taken at 240V, we determine QUANT as follows: 1 240 ⋅ 1 100 QUANT = − = −11339 600 ⋅ 208 ⋅ 7.4162 ⋅ 10 −10 QUANT is to be written to the CE location 0x2F. It does not matter which current value is chosen as long as the corresponding error value is significant (5% error at 0.2A used in the above equation will produce the same result for QUANT). Input noise and truncation can cause similar errors in the VAR calculation that can be eliminated using the QUANT_VAR variable. QUANT_VAR is determined using the same formula as QUANT. Page: 53 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.3 POWER SAVING MEASURES In many cases, especially when operating the TERIDIAN 71M6513/71M6513H from a battery, it is desirable to reduce the power consumed by the chip to a minimum. This can be achieved with the measures listed in Table 2-1. Power Saving Measure Software Control Typical Savings Disable the CE CE_EN = 0 0.16mA Disable the ADC ADC_DIS = 1 1.8mA Disable clock test output CKTEST CKOUTDIS = 1 0.6mA Disable emulator clock ECK_DIS = 1 0.1mA Set flash read pulse timing to 33 ns FLASH66Z =1 0.04mA Disable the LCD voltage boost circuitry LCD_BSTEN = 0 0.9mA Disable RTM outputs RTM_EN = 0 0.01mA Disable SSI output SSI_EN = 0 Select DGND for the multiplexer input TMUX[3:0] = 0 Disable reference voltage output VREF_DIS = 1 Reduce the clock for the MPU MPU_DIV = 5 0.4mA Table 2-1: Power Saving Measures Page: 54 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.4 SCHEMATIC INFORMATION In this section, hints on proper schematic design are provided that will help designing circuits that are functional and sufficiently immune to EMI (electromagnetic interference). 2.4.1 COMPONENTS FOR THE V1 PIN The V1 pin of the 71M6513/6513H can never be left unconnected. A voltage divider should be used to establish that V1 is in a safe range when the meter is in mission mode (V1 must be lower than 2.9V in all cases in order to keep the hardware watchdog timer enabled). For proper debugging or loading code into the 71M6513/6513H mounted on a PCB, it is necessary to have a provision like the header JP1 shown above R1 in Figure 2-7. A shorting jumper on this header pulls V1 up to V3P3 disabling the hardware watchdog timer. JP1 V3P3 2 R1 10K 1 HDR 1x2 L1 V1 D10 FERRITE UCLAMP3301D R2 21.5K C1 10uF C2 1000pF GND Figure 2-7: Voltage Divider for V1 On the 6513 Demo Boards this feature is implemented with resistors R83/R86, capacitor C31 (D6513T3C1 Demo Board) and TP10. See the board schematics in the Appendix for details. 2.4.2 RESET CIRCUIT Even though a functional meter will not necessarily need a reset switch, the 71M6513 Demo Boards provide a reset pushbutton that can be used when prototyping and debugging software. When a circuit is used in an EMI environment, the RESETZ pin should be supported by the external components shown in Figure 2-8. R1 should be in the range of 200Ω, R2 should be around 10Ω. The capacitor C1 should be 1nF. R1 and C1 should be mounted as close as possible to the IC. In cases where the trace from the pushbutton switch to the RESETZ pin poses a problem, R2 can be removed. V3P3 R1 200 SW1 R3 PB-SW R2 10 RESETZ 0 C2 0.1uF C1 1000pF GND Figure 2-8: External Components for RESETZ Page: 55 of 112 © 2005-2006 TERIDIAN Semiconductor Corporation Revision 5.6 71M6513/71M6513H Demo Board User’s Manual 2.4.3 OSCILLATOR The oscillator of the 71M6513 drives a standard 32.768kHz watch crystal (see Figure 2-9). Crystals of this type are accurate and do not require a high current oscillator circuit. The oscillator in the 71M6513 has been designed specifically to handle watch crystals and is compatible with their high impedance and limited power handling capability. The oscillator power dissipation is very low to maximize the lifetime of any battery backup device attached to the VBAT pin. 71M651X 10pF XIN crystal XOUT 10pF Figure 2-9: Oscillator Circuit It is not necessary to place an external resistor across the crystal, i.e. R91 on the D6513T3B2 Demo Board must not be populated. Capacitor values for the crystal must be