CS5463

CS5463 Single Phase, Bi-directional Power/Energy IC Features Energy Data Linearity: ±0.1% of Reading over 1000:1 Dynamic Range On-chip Functions: - Instantaneous Voltage, Current, and Power - IRMS and VRMS, Apparent, Reactive, and Active (Real) Power - Active Fundamental and Harmonic Power - Reactive Fundamental, Power Factor, and Line Frequency - Energy-to-pulse Conversion - System Calibrations and Phase Compensation - Temperature Sensor Description The CS5463 is an integrated power measurement device which combines two ∆Σ analog-to-digital converters, power calculation engine, energy-to-frequency converter, and a serial interface on a single chip. It is designed to accurately measure instantaneous current and voltage, and calculate VRMS, IRMS, instantaneous power, apparent power, active power, and reactive power for single-phase, 2- or 3-wire power metering applications. The CS5463 is optimized to interface to shunt resistors or current transformers for current measurement, and to resistive dividers or potential transformers for voltage measurement. The CS5463 features a bi-directional serial interface for communication with a processor and a programmable energy-to-pulse output function. Additional features include on-chip functionality to facilitate system-level calibration, temperature sensor, voltage sag detection, and phase compensation. ORDERING INFORMATION: See Page 45. VD+ Meets accuracy spec for IEC, ANSI, JIS. Low Power Consumption Current Input Optimized for Sense Resistor. GND-referenced Signals with Single Supply On-chip 2.5 V Reference (25 ppm/°C typ) Power Supply Monitor Simple Three-wire Digital Serial Interface “Auto-boot” Mode from Serial E2PROM Power Supply Configurations: VA+ = +5 V; AGND = 0 V; VD+ = +3.3 V to +5 V VA+ RESET IIN+ IIN- PGA 4th Order ∆Σ Modulator Digital Filter HPF Option MODE CS SDI VREFIN x1 Temperature Sensor Power Calculation Engine Serial Interface SDO SCLK INT VIN+ VIN- x10 2nd Order ∆Σ Modulator Digital Filter HPF Option E-to-F E1 E2 E3 VREFOUT Voltage Reference Power Monitor System Clock /K Clock Generator Calibration AGND PFMON XIN XOUT CPUCLK DGND http://www.cirrus.com Copyright © Cirrus Logic, Inc. 2008 (All Rights Reserved) APR ‘08 DS678F2 CS5463 TABLE OF CONTENTS 1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3. Characteristics & Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4. Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.1 Digital Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 Voltage and Current Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Power Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Linearity Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 14 14 15 5. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.1 Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.1.1 Voltage Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.1.2 Current Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.2 IIR Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 High-pass Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 Performing Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 Energy Pulse Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 16 16 17 5.5.1 Active Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.2 Apparent Energy Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.3 Reactive Energy Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.4 Voltage Channel Sign Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.5 PFMON Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.6 Design Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.6 Sag and Fault Detect Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.7 No Load Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.8 On-chip Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9 Voltage Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.10 System Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11 Power-down States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.12 Oscillator Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.13 Event Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 18 18 18 19 19 19 19 19 20 20 20 20 21 5.13.1 Typical Interrupt Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 5.14 Serial Port Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 5.14.1 Serial Port Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 5.15 Register Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16 Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.1 Start Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.2 SYNC0 and SYNC1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.3 Power-up/Halt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.4 Power-down and Software Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.5 Register Read/Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.16.6 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 Page 0 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.1 Configuration Register ( Config ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.2 Current and Voltage DC Offset Register ( IDCoff , VDCoff ) . . . . . . . . . . . . 6.1.3 Current and Voltage Gain Register ( Ign , Vgn ) . . . . . . . . . . . . . . . . . . . . 6.1.4 Cycle Count Register ( Cycle Count ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.5 PulseRateE Register ( PulseRateE ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.6 Instantaneous Current, Voltage, and Power Registers ( I , V , P ) . . . . . . 22 23 23 23 23 23 24 25 26 26 27 27 27 27 28 6. Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2 DS678F2 CS5463 6.1.7 Active (Real) Power Register ( PActive ) . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.8 RMS Current & Voltage Registers ( IRMS , VRMS ) . . . . . . . . . . . . . . . . . . 6.1.9 Epsilon Register ( e ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.10 Power Offset Register ( Poff ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.11 Status Register and Mask Register ( Status , Mask ) . . . . . . . . . . . . . . . 6.1.12 Current and Voltage AC Offset Register ( VACoff , IACoff ) . . . . . . . . . . . 6.1.13 Operational Mode Register ( Mode ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.14 Temperature Register ( T ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.15 Average and Instantaneous Reactive Power Register ( QAVG , Q ) . . . . 6.1.16 Peak Current and Peak Voltage Register ( Ipeak , Vpeak ) . . . . . . . . . . . . 6.1.17 Reactive Power Register ( QTrig ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.18 Power Factor Register ( PF ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.19 Apparent Power Register ( S ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.20 Control Register ( Ctrl ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.21 Harmonic Active Power Register ( PH ) . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.22 Fundamental Active Power Register ( PF ) . . . . . . . . . . . . . . . . . . . . . . 6.1.23 Fundamental Reactive Power Register ( QH ) . . . . . . . . . . . . . . . . . . . . 6.1.24 Page Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 Page 1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.1 Energy Pulse Output Width ( PulseWidth ) . . . . . . . . . . . . . . . . . . . . . . . . 6.2.2 No Load Threshold ( LoadMin ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.3 Temperature Gain Register ( TGain ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.4 Temperature Offset Register ( TOff ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 Page 3 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.1 Voltage Sag & Current Fault Duration Registers . . . . . . . . . . . . . . . . . . . 6.3.2 Voltage Sag & Current Fault Level Registers . . . . . . . . . . . . . . . . . . . . . . . 28 28 28 29 29 30 30 31 31 31 32 32 32 33 33 33 34 34 35 35 35 35 35 36 36 36 7. System Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 7.1 Channel Offset and Gain Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 7.1.1 Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1.1.1 Duration of Calibration Sequence . . . . . . . . . . . . . . . . . . . . . 7.1.2 Offset Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1.2.1 DC Offset Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . 7.1.2.2 AC Offset Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . 7.1.3 Gain Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1.3.1 AC Gain Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . . 7.1.3.2 DC Gain Calibration Sequence . . . . . . . . . . . . . . . . . . . . . . . 7.1.4 Order of Calibration Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . 37 37 37 37 38 38 38 39 39 8. Auto-boot Mode Using E2PROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 7.2 Phase Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 7.3 Active Power Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 8.1 Auto-boot Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 8.2 Auto-boot Data for E2PROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 8.3 Which E2PROMs Can Be Used? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 9. Basic Application Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10. Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11. Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12. Environmental, Manufacturing, & Handling Information . . . . . . . . . . . . . . . . . 13. Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 44 45 45 46 DS678F2 3 CS5463 LIST OF FIGURES Figure 1. CS5463 Read and Write Timing Diagrams.................................................................. 12 Figure 2. Timing Diagram for E1, E2, and E3 ............................................................................... 13 Figure 3. Data Measurement Flow Diagram. .............................................................................. 14 Figure 4. Power Calculation Flow. .............................................................................................. 15 Figure 5. Active and Reactive Energy Pulse Outputs ................................................................. 17 Figure 6. Apparent Energy Pulse Outputs .................................................................................. 18 Figure 7. Voltage Channel Sign Pulse outputs ........................................................................... 18 Figure 8. PFMON Output to Pin E3 ............................................................................................. 19 Figure 9. Sag and Fault Detect ................................................................................................... 19 Figure 10. Oscillator Connection................................................................................................. 20 Figure 11. CS5463 Memory Map ................................................................................................ 22 Figure 12. Calibration Data Flow ................................................................................................ 37 Figure 13. System Calibration of Offset ...................................................................................... 37 Figure 14. System Calibration of Gain. ....................................................................................... 38 Figure 15. Example of AC Gain Calibration ................................................................................ 38 Figure 16. Example of AC Gain Calibration ................................................................................ 38 Figure 17. Typical Interface of E2PROM to CS5463................................................................... 40 Figure 18. Typical Connection Diagram (Single-phase, 2-wire).................................................. 41 Figure 20. Typical Connection Diagram (Single-phase, 3-wire).................................................. 42 Figure 19. Typical Connection Diagram (Single-phase, 2-wire – Isolated from Power Line) ...... 42 Figure 21. Typical Connection Diagram (Single-phase, 3-wire – No Neutral Available) ............. 43 LIST OF TABLES Table 1. Current Channel PGA Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 2. E2 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 3. E3 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 4. Interrupt Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4 DS678F2 CS5463 1. OVERVIEW The CS5463 is a CMOS monolithic power measurement device with a computation engine and an energy-to-frequency pulse output. The CS5463 combines a programmable gain amplifier, two ∆Σ Analog-to-Digital Converters (ADCs), system calibration, and a computation engine on a single chip. The CS5463 is designed for power measurement applications and is optimized to interface to a current sense resistor or transformer for current measurement, and to a resistive divider or potential transformer for voltage measurement. The current channel provides programmable gains to accommodate various input levels from a multitude of sensing elements. With single +5 V supply on VA+/AGND, both of the CS5463’s input channels can accommodate common mode plus signal levels between (AGND - 0.25 V) and VA+. The CS5463 also is equipped with a computation engine that calculates instantaneous power, IRMS, VRMS, apparent power, active (real) power, reactive power, harmonic active power, active and reactive fundamental power, and power factor. The CS5463 additional features include line frequency, current and voltage sag detection, zero-cross detection, positive-only accumulation mode, and three programmable pulse output pins. To facilitate communication to a microprocessor, the CS5463 includes a simple three-wire serial interface which is SPI™ and Microwire™ compatible. The CS5463 provides three outputs for energy registration. E1, E2, and E3 are designed to interface to a microprocessor. DS678F2 5 CS5463 2. PIN DESCRIPTION Crystal Out XOUT CPU Clock Output CPUCLK Positive Digital Supply VD+ Digital Ground DGND Serial Clock SCLK Serial Data Ouput SDO Chip Select CS Mode Select MODE Differential Voltage Input VIN+ Differential Voltage Input VINVoltage Reference Output VREFOUT Voltage Reference Input VREFIN 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 XIN SDI E2 E1 INT RESET E3 PFMON IIN+ IINVA+ AGND Crystal In Serial Data Input Energy Output 2 Energy Output 1 Interrupt Reset High Frequency Energy Output Power Fail Monitor Differential Current Input Differential Current Input Positive Analog Supply Analog Ground Clock Generator Crystal Out Crystal In CPU Clock Output Control Pins and Serial Data I/O Serial Clock Input Serial Data Output Chip Select Mode Select Energy Output 5 6 7 8 SCLK – A Schmitt-trigger input pin. Clocks data from the SDI pin into the receive buffer and out of the transmit buffer onto the SDO pin when CS is low. SDO – Serial port data output pin.SDO is forced into a high-impedance state when CS is high. CS – Low, activates the serial port interface. MODE - High, enables the “auto-boot” mode. The mode pin has an internal pull-down resistor. figurable outputs for active, apparent, and reactive power, negative energy indication, zero cross detection, and power failure monitoring. E1, E2, E3 outputs are configured in the Operational Modes Register. 1,24 XOUT, XIN – The output and input of an inverting amplifier. Oscillation occurs when connected to a crystal, providing an on-chip system clock. Alternatively, an external clock can be supplied to the XIN pin to provide the system clock for the device. CPUCLK – Output of on-chip oscillator which can drive one standard CMOS load. 2 18,21,22 E3, E1, E2 – Active-low pulses with an output frequency proportional to the selected power. Con- Reset Interrupt Serial Data Input Analog Inputs/Outputs Differential Voltage Inputs Differential Current Inputs Voltage Reference Output Voltage Reference Input Power Supply Connections Positive Digital Supply Digital Ground Positive Analog Supply Analog Ground Power Fail Monitor 19 20 23 RESET – A Schmitt-trigger input pin. Low activates Reset, all internal registers (some of which drive output pins) are set to their default states. INT - Low, indicates that an enabled event has occurred. SDI - Serial port data input pin. Data will be input at a rate determined by SCLK. 9,10 15,16 11 12 VIN+, VIN- – Differential analog input pins for the voltage channel. IIN+, IIN- – Differential analog input pins for the current channel. VREFOUT – The on-chip voltage reference output. The voltage reference has a nominal magnitude of 2.5 V and is referenced to the AGND pin on the converter. VREFIN – The input to this pin establishes the voltage reference for the on-chip modulator. 3 4 14 13 VD+ – The positive digital supply. DGND – Digital Ground. VA+ – The positive analog supply. AGND – Analog ground. PFMON – The power fail monitor pin monitors the analog supply. If the analog supply does not meet or falls below PFMON’s voltage threshold, a Low-supply Detect (LSD) event is set in the status register. 17 6 DS678F2 CS5463 3. CHARACTERISTICS & SPECIFICATIONS RECOMMENDED OPERATING CONDITIONS Parameter Positive Digital Power Supply Positive Analog Power Supply Voltage Reference Specified Temperature Range Symbol VD+ VA+ VREFIN TA Min 3.135 4.75 -40 Typ 5.0 5.0 2.5 Max 5.25 5.25 +85 Unit V V V °C ANALOG CHARACTERISTICS • • • • Min / Max characteristics and specifications are guaranteed over all Recommended Operating Conditions. Typical characteristics and specifications are measured at nominal supply voltages and TA = 25 °C. VA+ = VD+ = 5 V ±5%; AGND = DGND = 0 V; VREFIN = +2.5 V. All voltages with respect to 0 V. MCLK = 4.096 MHz. Parameter Accuracy Symbol PActive QAvg PF Min Typ Max Unit Active Power (Note 1) Average Reactive Power (Note 1 and 2) Power Factor (Note 1 and 2) Current RMS (Note 1) Voltage RMS (Note 1) Analog Inputs (Both Channels) All Gain Ranges Input Range 0.1% - 100% All Gain Ranges Input Range 0.1% - 100% All Gain Ranges Input Range 1.0% - 100% Input Range 0.1% - 1.0% All Gain Ranges Input Range 0.2% - 100% Input Range 0.1% - 0.2% All Gain Ranges Input Range 5% - 100% (DC, 50, 60 Hz) All Gain Ranges (Gain = 10) (Gain = 50) (Gain = 50) (50, 60 Hz) (Gain = 10) (Gain = 50) (Gain = 10) (Gain = 50) (Note 3) 80 -0.25 80 30 - ±0.1 ±0.2 ±0.2 ±0.27 ±0.2 ±1.5 ±0.1 500 100 94 -115 32 52 22.5 4.5 4.0 ±0.4 VA+ - % % % % % % % % dB V mVP-P mVP-P dB dB pF pF kΩ µVrms µVrms µV/°C % IRMS VRMS CMRR Common Mode Rejection Common Mode + Signal Analog Inputs (Current Channel) Differential Input Range [(IIN+) - (IIN-)] Total Harmonic Distortion Crosstalk with Voltage Channel at Full Scale Input Capacitance Effective Input Impedance Noise (Referred to Input) Offset Drift (Without the High Pass Filter) Gain Error IIN THD IC EII NI OD GE Notes: 1. Applies when the HPF option is enabled. 2. Applies when the line frequency is equal to the product of the Output Word Rate (OWR) and the value of epsilon (ε). DS678F2 7 CS5463 ANALOG CHARACTERISTICS (Continued) Parameter Analog Inputs (Voltage Channel) Symbol [(VIN+) - (VIN-)] VIN THD IC EII NV OD GE T PSCA PSCD PSCD PC Min 65 2 45 70 2.3 - Typ 500 75 -70 0.2 140 16.0 ±3.0 ±5 1.1 2.9 1.7 21 11.6 8 10 65 75 2.45 2.55 Max - Unit mVP-P dB dB pF MΩ µVrms µV/°C % °C mA mA mA mW mW mW µW dB dB V V Differential Input Range Total Harmonic Distortion Crosstalk with Current Channel at Full Scale (50, 60 Hz) Input Capacitance All Gain Ranges Effective Input Impedance Noise (Referred to Input) Offset Drift (Without the High Pass Filter) Gain Error Temperature Channel (Note 3) Temperature Accuracy Power Supplies 29 17.5 2.7 Power Supply Currents (Active State) IA+ ID+ (VA+ = VD+ = 5 V) ID+ (VA+ = 5 V, VD+ = 3.3 V) Power Consumption Active State (VA+ = VD+ = 5 V) (Note 4) Active State (VA+ = 5 V, VD+ = 3.3 V) Stand-by State Sleep State Power Supply Rejection Ratio (50, 60 Hz) (Note 5) Voltage Channel Current Channel PFMON Low-voltage Trigger Threshold (Note 6) PFMON High-voltage Power-on Trip Point (Note 7) Notes: 3. Applies before system calibration. 4. All outputs unloaded. All inputs CMOS level. PSRR PMLO PMHI 5. Measurement method for PSRR: VREFIN tied to VREFOUT, VA+ = VD+ = 5 V, a 150 mV (zero-to-peak) (60 Hz) sinewave is imposed onto the +5 V DC supply voltage at VA+ and VD+ pins. The “+” and “-” input pins of both input channels are shorted to AGND. Then the CS5463 is commanded to continuous conversion acquisition mode, and digital output data is collected for the channel under test. The (zero-to-peak) value of the digital sinusoidal output signal is determined, and this value is converted into the (zero-to-peak) value of the sinusoidal voltage (measured in mV) that would need to be applied at the channel’s inputs, in order to cause the same digital sinusoidal output. This voltage is then defined as Veq. PSRR is then (in dB): 150 PSRR = 20 ⋅ log --------V eq 6. When voltage level on PFMON is sagging, and LSD bit = 0, the voltage at which LSD is set to 1. 7. If the LSD bit has been set to 1 (because PFMON voltage fell below PMLO), this is the voltage level on PFMON at which the LSD bit can be permanently reset back to 0. 8 DS678F2 CS5463 VOLTAGE REFERENCE Parameter Reference Output Symbol VREFOUT (Note 8) (Note 9) TCVREF ∆ VR VREFIN Min +2.4 +2.4 - Typ +2.5 25 6 +2.5 4 25 Max +2.6 60 10 +2.6 - Unit V ppm/°C mV V pF nA Output Voltage Temperature Coefficient Load Regulation Reference Input Input Voltage Range Input Capacitance Input CVF Current Notes: 8. The voltage at VREFOUT is measured across the temperature range. From these measurements the following formula is used to calculate the VREFOUT Temperature Coefficient:. TC VREF = V REFOUT ( (VREFOUT - UT VREFO MAX AVG MIN ) (T A MAX 1 - T AM IN ( 1.0 x 10 6 9. Specified at maximum recommended output of 1 µA, source or sink. DIGITAL CHARACTERISTICS • • • • Min / Max characteristics and specifications are guaranteed over all Recommended Operating Conditions. Typical characteristics and specifications are measured at nominal supply voltages and TA = 25 °C. VA+ = VD+ = 5V ±5%; AGND = DGND = 0 V. All voltages with respect to 0 V. MCLK = 4.096 MHz. Parameter Master Clock Characteristics Symbol Min 2.5 40 40 -2.8 - Master Clock Frequency Master Clock Duty Cycle CPUCLK Duty Cycle Filter Characteristics Internal Gate Oscillator (Note 11) MCLK (Note 12 and 13) (Voltage Channel, 60 Hz) DCLK = MCLK/K (Both Channels) -3 dB (Note 15) VIH OWR 4.096 DCLK/8 DCLK/1024 0.5 1.0 Phase Compensation Range Input Sampling Rate Digital Filter Output Word Rate High-pass Filter Corner Frequency 25 Full-scale DC Calibration Range (Referred to Input) (Note 14) FSCR Channel-to-channel Time-shift Error Input/Output Characteristics High-level Input Voltage All Pins Except XIN and SCLK and RESET XIN SCLK and RESET Low-level Input Voltage (VD = 5 V) All Pins Except XIN and SCLK and RESET XIN SCLK and RESET 0.6 VD+ (VD+) - 0.5 0.8 VD+ VIL - DS678F2 ( Typ Max 20 60 60 +2.8 100 Unit MHz % % ° Hz Hz Hz %F.S. µs 0.8 1.5 0.2 VD+ V V V V V V 9 ( ( CS5463 Parameter Low-level Input Voltage (VD = 3.3 V) All Pins Except XIN and SCLK and RESET XIN SCLK and RESET High-level Output Voltage Low-level Output Voltage Input Leakage Current 3-state Leakage Current Digital Output Pin Capacitance Iout = +5 mA Iout = -5 mA (Note 16) Symbol VIL VOH VOL Iin IOZ Cout (VD+) - 1.0 ±1 5 0.48 0.3 0.2 VD+ 0.4 ±10 ±10 V V V V V µA µA pF Min Typ Max Unit Notes: 10. All measurements performed under static conditions. 11. If a crystal is used, then XIN frequency must remain between 2.5 MHz - 5.0 MHz. If an external oscillator is used, XIN frequency range is 2.5 MHz - 20 MHz, but K must be set so that MCLK is between 2.5 MHz - 5.0 MHz. 12. If external MCLK is used, then the duty cycle must be between 45% and 55% to maintain this specification. 13. The frequency of CPUCLK is equal to MCLK. 14. The minimum FSCR is limited by the maximum allowed gain register value. The maximum FSCR is limited by the full-scale signal applied to the channel input. 15. Configuration Register bits PC[6:0] are set to “0000000”. 16. The MODE pin is pulled low by an internal resistor. 10 DS678F2 CS5463 SWITCHING CHARACTERISTICS • • • • Min / Max characteristics and specifications are guaranteed over all Recommended Operating Conditions. Typical characteristics and specifications are measured at nominal supply voltages and TA = 25 °C. VA+ = 5 V ±5% VD+ = 3.3 V ±5% or 5 V ±5%; AGND = DGND = 0 V. All voltages with respect to 0 V. Logic Levels: Logic 0 = 0 V, Logic 1 = VD+. Parameter Rise Times (Note 17) Fall Times (Note 17) Start-up Symbol trise Min 200 200 Typ 50 50 60 - Max 1.0 100 1.0 100 2 - Unit µs µs ns µs µs ns ms MHz ns ns Any Digital Input Except SCLK SCLK Any Digital Output Any Digital Input Except SCLK SCLK Any Digital Output XTAL = 4.096 MHz (Note 18) tfall Oscillator Start-up Time Serial Port Timing tost SCLK Serial Clock Frequency Serial Clock SDI Timing Pulse Width High Pulse Width Low t1 t2 t3 t4 t5 t6 t7 t8 CS Falling to SCLK Rising Data Set-up Time Prior to SCLK Rising Data Hold Time After SCLK Rising SDO Timing 50 50 100 - 20 20 20 8 8 50 50 50 ns ns ns ns ns ns MCLK MCLK ns MCLK CS Falling to SDI Driving SCLK Falling to New Data Bit (hold time) CS Rising to SDO Hi-Z Auto-Boot Timing Serial Clock MODE setup time to RESET Rising RESET rising to CS falling CS falling to SCLK rising SCLK falling to CS rising Pulse Width Low Pulse Width High t9 t10 t11 t12 t13 t14 t15 t16 50 100 50 48 100 8 16 MCLK MCLK ns ns CS rising to driving MODE low (to end auto-boot sequence) SDO guaranteed setup time to SCLK rising Notes: 17. Specified using 10% and 90% points on waveform of interest. Output loaded with 50 pF. 18. Oscillator start-up time varies with crystal parameters. This specification does not apply when using an external clock source. DS678F2 11 CS5463 t3 CS t1 t2 SC LK t4 MSB-1 MSB-1 MSB MSB LSB t5 MSB-1 MSB-1 MSB MSB LSB LSB LSB L o w B y te L o w B y te MSB-1 MSB LSB LSB t8 t15 t14 t7 STOP bit Last 8 B it s SDI C o m m a n d T im e 8 S C L K s H ig h B y te M id B y te SDI Write Timing (Not to Scale) CS t6 MSB-1 MSB H ig h B y te MSB-1 MSB LSB M id B y te SDO UNKNOW N t1 t2 t7 SC LK MSB-1 MSB SDI C o m m a n d T im e 8 S C L K s LSB SYN C 0 or SYN C 1 C om m and SYN C 0 or SYN C1 C om m and SYN C 0 or SYN C1 C om m and SDO Read Timing (Not to Scale) t11 MODE ( IN P U T ) RESET ( IN P U T ) t12 t13 CS (O U T P U T ) SCLK (O U T P U T ) t10 t16 t9 t4 t5 SDO (O U T P U T ) SDI ( IN P U T ) D a ta fro m E E P R O M Auto-boot Sequence Timing (Not to Scale) Figure 1. CS5463 Read and Write Timing Diagrams 12 DS678F2 CS5463 SWITCHING CHARACTERISTICS (Continued) Parameter E1, E2, and E3 Timing (Note 19 and 20) Period Pulse Width Rising Edge to Falling Edge E2 Setup to E1 and/or E3 Falling Edge E1 Falling Edge to E3 Falling Edge tperiod tpw t3 t4 t5 250 244 6 1.5 248 µs µs µs µs µs Symbol Min Typ Max Unit Notes: 19. Pulse output timing is specified at MCLK = 4.096 MHz, E2MODE = 0, and E3MODE[1:0] = 0. Refer to Section 5.5 Energy Pulse Output on page 17 for more information on pulse output pins. 20. Timing is proportional to the frequency of MCLK. tpw E1 E2 tperiod t3 t4 tpw t5 tperiod t3 t5 t4 E3 Figure 2. Timing Diagram for E1, E2, and E3 ABSOLUTE MAXIMUM RATINGS WARNING: Operation at or beyond these limits may result in permanent damage to the device. Normal operation is not guaranteed at these extremes. Parameter DC Power Supplies (Notes 21 and 22) Positive Digital Positive Analog (Notes 23, 24, 25) (Note 26) All Analog Pins All Digital Pins Symbol VD+ VA+ IIN IOUT PD VINA VIND TA Tstg Min -0.3 -0.3 - 0.3 -0.3 -40 -65 Typ Max +6.0 +6.0 ±10 100 500 (VA+) + 0.3 (VD+) + 0.3 85 150 Unit V V mA mA mW V V °C °C Input Current, Any Pin Except Supplies Power Dissipation Analog Input Voltage Digital Input Voltage Ambient Operating Temperature Storage Temperature Output Current, Any Pin Except VREFOUT Notes: 21. VA+ and AGND must satisfy [(VA+) - (AGND)] ≤ + 6.0 V. 22. VD+ and AGND must satisfy [(VD+) - (AGND)] ≤ + 6.0 V. 23. Applies to all pins including continuous over-voltage conditions at the analog input pins. 24. Transient current of up to 100 mA will not cause SCR latch-up. 25. Maximum DC input current for a power supply pin is ±50 mA. 26. Total power dissipation, including all input currents and output currents. DS678F2 13 CS5463 Digital Filter VOLTAGE VDCoff* Vgn * MUX x10 2nd Order ∆Σ Modulator DELAY REG SINC 3 X DELAY REG IIR + + MUX APF HPF HPF Σ V* VQ* X + X Σ + X Q* 6 ε* SYSGain * 2322 X ∫ PC6 PC5 PC4 PC3 PC2 PC1 PC0 Configuration Register * ... XVDEL XIDEL VHPF 8 7 6 IHPF 5 IIR 4 321 0 Operational Modes Register * 2π X P* MUX CURRENT PGA 4th Order ∆Σ Modulator MUX SINC 3 DELAY REG X DELAY REG IIR + Σ + X I gn* HPF APF I* * DENOTES REGISTER NAME. Digital Filter IDCoff* Figure 3. Data Measurement Flow Diagram. 4. THEORY OF OPERATION The CS5463 is a dual-channel analog-to-digital converter (ADC) followed by a computation engine that performs power calculations and energy-to-pulse conversion. The data flow for the voltage and current channel measurement and the power calculation algorithms are depicted in Figure 3 and 4, respectively. The analog inputs are structured with two dedicated channels, Voltage and Current, then optimized to simplify interfacing to various sensing elements. The voltage-sensing element introduces a voltage waveform on the voltage channel input VIN± and is subject to a gain of 10x. A second-order delta-sigma modulator samples the amplified signal for digitization. Simultaneously, the current-sensing element introduces a voltage waveform on the current channel input IIN± and is subject to two selectable gains of the programmable gain amplifier (PGA). The amplified signal is sampled by a fourth-order delta-sigma modulator for digitization. Both converters sample at a rate of MCLK/8, the over-sampling provides a wide dynamic range and simplified anti-alias filter design. from the calculated VRMS and I RMS as well as the apparent power. When the optional HPF in either channel is disabled, an all-pass filter (APF) is implemented. The APF has an amplitude response that is flat within the channel bandwidth and is used for matching phase in systems where only one HPF is engaged. 4.2 Voltage and Current Measurements The digital filter output word is then subject to a DC offset adjustment and a gain calibration (See Section 7. System Calibration on page 37). The calibrated measurement is available by reading the instantaneous voltage and current registers. The Root Mean Square (RMS in Figure 4) calculations are performed on N instantaneous voltage and current samples, Vn and In, respectively (where N is the cycle count), using the formula: I RMS = 4.1 Digital Filters The decimating digital filters on both channels are Sinc3 filters followed by 4th-order IIR filters. The single-bit data is passed to the low-pass decimation filter and output at a fixed word rate. The output word is passed to an optional IIR filter to compensate for the magnitude roll off of the low-pass filtering operation. An optional digital high-pass filter (HPF in Figure 3) removes any DC component from the selected signal path. By removing the DC component from the voltage and/or the current channel, any DC content will also be removed from the calculated active power as well. With both HPFs enabled the DC component will be removed 14 ∑ In n=0 -------------------N N–1 and likewise for VRMS, using Vn. IRMS and VRMS are accessible by register reads, which are updated once every cycle count (referred to as a computational cycle). 4.3 Power Measurements The instantaneous voltage and current samples are multiplied to obtain the instantaneous power (see Figure 3). The product is then averaged over N conversions to compute active power and is used to drive energy pulse output E1. Energy output E2 is selectable, providing an energy sign or a pulse output that is proportional to the apparent power. Energy output E3 DS678F2 CS5463 VACoff* V* X Σ N ÷N √ √ Energy-to-pulse + + Σ X V RMS* S* X IACoff* I* X + Σ - Σ N X ÷N + + √ QTRIG * Σ E1 E2 I RMS* Inverse X PF* P* off PulseRate * E3 + P* + Σ Q* Σ Σ N N ÷N ÷N * PACTIVE X * QAVG *DENOTES REGISTER NAME. Figure 4. Power Calculation Flow. provides a pulse output that is proportional to the reactive power or apparent power. Output E3 can also be set to display the sign of the voltage applied to the voltage channel or the PFMON comparator output. The apparent power (S) is the combination of the active power and reactive power, without reference to an impedance phase angle, and is calculated by the CS5463 using the following formula: S = V RMS × I RMS quadrature power (Q). The product is then averaged over N conversions, utilizing the formula N ∑ Qn n=1 Q Avg = -----------------------N Fundamental active (PF) and reactive (QF) power is calculated by performing a discrete Fourier transform (DFT) at the relevant frequency on the instantaneous voltage (V) and current (I). Epsilon is used to set the frequency of the internal sine (imaginary component) and cosine (real component) waveform generator. The harmonic active power (PH) is calculated by subtracting the fundamental active power (PF) from the active power (PActive). The peak current (Ipeak) and peak voltage (Vpeak) are the instantaneous current and voltage, respectively, with the greatest magnitude detected during the last computation cycle. Active, apparent, reactive, and fundamental power are updated every computation cycle. Power Factor (PF) is the active power (PActive) divided by the apparent power (S) P Active PF = ----------------S The sign of the power factor is determined by the active power. The CS5463 calculates the reactive power, QTrig utilizing trigonometric identities, giving the formula Q Trig = 2 S 2 – P Active 4.4 Linearity Performance The linearity of the VRMS, I RMS, active, reactive, and power-factor power measurements (before calibration) will be within ±0.1% of reading over the ranges specified, with respect to the input voltage levels required to cause full-scale readings in the IRMS and VRMS registers. Refer to Accuracy Specifications on page 7. Until the CS5463 is calibrated, the accuracy of the CS5463 (with respect to a reference line-voltage and line-current level on the power mains) is not guaranteed to within ±0.1%. (See Section 7. System Calibration on page 37.) The accuracy of the internal calculations can often be improved by selecting a value for the Cycle Count Register that will cause the time duration of one computation cycle to be equal to (or very close to) a whole number of power-line cycles (and N must be greater than or equal to 4000). 15 Average reactive power, QAvg, is generated by averaging the voltage multiplied by the current with a 90° phase shift difference between them. The 90° phase shift is realized by applying an IIR digital filter in the voltage channel to obtain quadrature voltage (see Figure 3). This filter will give exactly -90° phase shift across all frequencies, and utilizes epsilon (ε) to achieve unity gain at the line frequency. The instantaneous quadrature voltage (VQ) and current (I) samples are multiplied to obtain the instantaneous DS678F2 CS5463 5. FUNCTIONAL DESCRIPTION 5.1 Analog Inputs The CS5463 is equipped with two fully differential input channels. The inputs VIN± and IIN± are designated as the voltage and current channel inputs, respectively. The full-scale differential input voltage for the current and voltage channel is ±250 mVP. applied to the voltage and/or current channel, the maximum input range should be adjusted accordingly. 5.2 IIR Filters The current and voltage channel are equipped with a 4th-order IIR filter, that is used to compensate for the magnitude roll off of the low-pass decimation filter. Operational Mode Register bit IIR engages the IIR filters in both the voltage and current channels. 5.1.1 Voltage Channel The output of the line voltage resistive divider or transformer is connected to the VIN+ and VIN- input pins of the CS5463. The voltage channel is equipped with a 10x fixed-gain amplifier. The full-scale signal level that can be applied to the voltage channel is ±250 mV. If the input signal is a sine wave the maximum RMS voltage at a gain 10x is: 250mV P 2 5.3 High-pass Filters By removing the offset from either channel, no error component will be generated at DC when computing the active power. By removing the offset from both channels, no error component will be generated at DC when computing VRMS, IRMS, and apparent power. Operational Mode Register bits VHPF and IHPF activate the HPF in the voltage and current channel respectively. When a high-pass filter is active in only one channel, an all-pass filter (APF) is applied to the other channel. The APF has an amplitude response that is flat within the channel bandwidth and is used for matching phase in systems where only one HPF is engaged. -------------------- ≅ 176.78mV - RMS which is approximately 70.7% of maximum peak voltage. The voltage channel is also equipped with a Voltage Gain Register, allowing for an additional programmable gain of up to 4x. 5.1.2 Current Channel The output of the current-sense resistor or transformer is connected to the IIN+ and IIN- input pins of the CS5463. To accommodate different current sensing elements the current channel incorporates a programmable gain amplifier (PGA) with two programmable input gains. Configuration Register bit Igain (see Table 1) defines the two gain selections and corresponding maximum input-signal level. Igain Maximum Input Range 5.4 Performing Measurements The CS5463 performs measurements of instantaneous voltage (Vn) and current (In), and calculates instantaneous power (Pn) at an output word rate (OWR) of ( MCLK ⁄ K ) OWR = ---------------------------1024 where K is the clock divider selected in the Configuration Register. The RMS voltage (VRMS), RMS current (IRMS), and active power (Pactive) are computed using N instantaneous samples of Vn, In, and Pn respectively, where N is the value in the Cycle Count Register and is referred to as a “computation cycle”. The apparent power (S) is the product of VRMS and IRMS. A computation cycle is derived from the master clock (MCLK), with frequency: OWR Computation Cycle = -------------N 0 1 ±250 mV ±50 mV 10x 50x Table 1. Current Channel PGA Setting For example, if Igain=0, the current channel’s PGA gain is set to 10x. If the input signals are pure sinusoids with zero phase shift, the maximum peak differential signal on the current or voltage channel is ±250 mVP. The input signal levels are approximately 70.7% of maximum peak voltage producing a full-scale energy pulse registration equal to 50% of absolute maximum energy pulse registration. This will be discussed further in See Section 5.5 Energy Pulse Output on page 17. The Current Gain Register also facilitates an additional programmable gain of up to 4x. If an additional gain is Under default conditions and with K = 1, N = 4000, and MCLK = 4.096 MHz – the OWR = 4000 Hz and the Computation Cycle = 1 Hz. All measurements are available as a percentage of full scale. The format for signed registers is a two’s complement, normalized value between -1 and +1. The format 16 DS678F2 CS5463 for unsigned registers is a normalized value between 0 and 1. A register value of 23 (2 – 1) ----------------------- = 0.99999988 23 2 the pulse output mode, which is controlled by bit E2MODE in the Operational Mode Register. E2MODE E2 Output Mode 0 1 Sign of Energy Apparent Energy represents the maximum possible value. At each instantaneous measurement, the CRDY bit will be set in the Status Register, and the INT pin will become active if the CRDY bit is unmasked in the Mask Register. At the end of each computation cycle, the DRDY bit will be set in the Status Register, and the INT pin will become active if the DRDY bit is unmasked in the Mask Register. When these bits are asserted, they must be cleared before they can be asserted again. If the Cycle Count Register (N) is set to 1, all output calculations are instantaneous, and DRDY, like CRDY, will indicate when instantaneous measurements are finished. Some calculations are inhibited when the cycle count is less than 2. Epsilon (ε) is the ratio of the input line frequency (fi) to the sample frequency (fs) of the ADC. Table 2. E2 Pin Configuration The E3 pin can be set to register Reactive Energy (default), PFMON, Voltage Channel Sign, or Apparent Energy. Table 3 defines the pulse output format, which is controlled by bits E3MODE[1:0] in the Operational Mode Register. E3MODE1 E3MODE0 E3 OutPut Mode 0 0 1 1 0 1 0 1 Reactive Energy PFMON Voltage Channel Sign Apparent Energy Table 3. E3 Pin Configuration ε = fi ⁄ fs where fs = MCLK / (K*1024). With MCLK = 4.096 MHz and clock divider K = 1, fs = 4000 Hz. For the two most-common line frequencies, 50 Hz and 60 Hz The pulse output frequency of E1, E2, and E3 is directly proportional to the power calculated from the input signals. The value contained in the PulseRateE Register is the ratio of the frequency of energy-output pulses to the number of samples, at full scale, which defines the average frequency for the output pulses. The pulse width, tpw in Figure 2, is programmable through the PulseWidth register, and is approximately equal to: 1 t pw ( sec ) ≅ PulseWidth • ----------------------------------------------( MCLK/K ) / 1024 ε and = 50 Hz ⁄ 4000 Hz = 0.0125 ε = 60 Hz ⁄ 4000 Hz = 0.015 If MCLK = 4.096 MHz, K = 1, and PulseWidth = 1, then tpw ≅ 0.25 ms. respectively. Epsilon is used to set the frequency of the internal sine/cosine reference for the fundamental active and reactive measurements, and the gain of the 90° phase shift (IIR) filter for the average reactive power. 5.5.1 Active Energy The E1 pin produces active-low pulses with an output frequency proportional to the active power. The E2 pin is the energy direction indicator. Positive energy is represented by E1 pin falling while the E2 is high. Negative energy is represented by the E1 pin falling while the E2 is low. The E1 and E2 switching characteristics are specified in Figure 2. Timing Diagram for E1, E2, and E3 on page13. Figure 5 illustrates the pulse output format with positive active energy and negative reactive energy. E1 E2 E3 5.5 Energy Pulse Output The CS5463 provides three output pins for energy registration. By default, E1 registers active energy, E3 registers reactive energy, and E2 indicates the sign of both active and reactive energy. (See Figure 2. Timing Diagram for E1, E2, and E3 on page13.) The E1 pulse output is designed to register the Active Energy. The E2 pin can be set to register Apparent Energy. Table 2 defines Figure 5. Active and Reactive energy pulse outputs DS678F2 17 CS5463 The pulse output frequency of E1 is directly proportional to the active power calculated from the input signals. To calculate the output frequency of E1, the following transfer function can be utilized: With MCLK = 4.096 MHz and default settings, the pulses will have an average frequency equal to the frequency specified by PulseRate when the input signals applied to the voltage and current channels cause full-scale readings in the instantaneous voltage and current registers. The maximum pulse frequency from the E2 (and/or E3) pin is (MCLK/K)/2048. The E2 (and/or E3) pin outputs apparent energy, but has no energy direction indicator. FREQ P VIN × VGAIN × IIN × IGAIN × PF × PulseRate = -------------------------------------------------------------------------------------------------------------------------------2 VREFIN FREQP = Average frequency of active energy E1 pulses [Hz] VIN = rms voltage across VIN+ and VIN- [V] VGAIN = Voltage channel gain IIN = rms voltage across IIN+ and IIN- [V] IGAIN = Current channel gain PF = Power Factor PulseRate = PulseRateE x (MCLK/K)/2048 [Hz] VREFIN = Voltage at VREFIN pin [V] 5.5.3 Reactive Energy Mode Reactive energy pulses are output on pin E3 by setting bit E3MODE[1:0] = 0 (default) in the Operational Mode Register. Positive reactive energy is registered by E3 falling when E2 is high. Negative reactive energy is registered by E3 falling when E2 is low. Figure 5 on page 17 illustrates the pulse output format with negative reactive energy output on pin E3 and the sign of the energy on E2. The E3 and E2 pulse output switching characteristics are specified in Figure 2 on page 13. The pulse output frequency of E3 is directly proportional to the reactive power calculated from the input signals. To calculate the output frequency on E3, the following transfer function can be utilized: VIN × VGAIN × IIN × IGAIN × PQ × PulseRate = --------------------------------------------------------------------------------------------------------------------------------2 VREFIN With MCLK = 4.096 MHz, PF = 1, and default settings, the pulses will have an average frequency equal to the frequency specified by PulseRate when the input signals applied to the voltage and current channels cause full-scale readings in the instantaneous voltage and current registers. The maximum pulse frequency from the E1 pin is (MCLK/K)/2048. 5.5.2 Apparent Energy Mode Pin E2 outputs apparent energy pulses when the Operational Mode Register bit E2MODE = 1. Pin E3 outputs apparent energy pulses when the Operational Mode Register bits E3MODE[1:0] = 3 (11b). Figure 6 illustrates the pulse output format with apparent energy on E2 (E2MODE = 1 and E3MODE[1:0] = 0) E1 E2 E3 FREQ Q FREQQ = Average frequency of reactive energy E3 pulses [Hz] VIN = rms voltage across VIN+ and VIN- [V] VGAIN = Voltage channel gain IIN = rms voltage across IIN+ and IIN- [V] IGAIN = Current channel gain PQ = 1 – PF2 PulseRate = PulseRateE x (MCLK/K)/2048 [Hz] VREFIN = Voltage at VREFIN pin [V] Figure 6. Apparent energy pulse outputs The pulse output frequency of E2 (and/or E3) is directly proportional to the apparent power calculated from the input signals. Since apparent power is without reference to an impedance phase angle, the following transfer function can be utilized to calculate the output frequency on E2 (and/or E3). VIN × VGAIN × IIN × IGAIN × PulseRate = -----------------------------------------------------------------------------------------------------------------S 2 VREFIN With MCLK = 4.096 MHz, PF = 0 and default settings, the pulses will have an average frequency equal to the frequency specified by PulseRate when the input signals applied to the voltage and current channels cause full-scale readings in the instantaneous voltage and current registers. The maximum pulse frequency from the E1 pin is (MCLK/K)/2048. 5.5.4 Voltage Channel Sign Mode Setting bits E3MODE[1:0] = 2 (10b) in the Operational Mode Register outputs the sign of the voltage channel on pin E3. Figure 7 illustrates the output format with voltage channel sign on E3 E1 E2 E3 FREQ FREQS = Average frequency of apparent energy E2 and/or E3 pulses [Hz] VIN = rms voltage across VIN+ and VIN- [V] VGAIN = Voltage channel gain IIN = rms voltage across IIN+ and IIN- [V] IGAIN = Current channel gain PulseRate = PulseRateE x (MCLK/K)/2048 [Hz] VREFIN = Voltage at VREFIN pin [V] Figure 7. Voltage Channel Sign Pulse outputs 18 DS678F2 CS5463 Output pin E3 is high when the line voltage is positive and pin E3 is low when the line voltage is negative. 5.6 Sag and Fault Detect Feature Status bit VSAG and IFAULT in the Status Register, indicates a sag occurred in the power line voltage and current, respectively. For a sag condition to be identified, the absolute value of the instantaneous voltage or current must be less than the sag level for more than half of the sag duration (see Figure 9). To activate voltage sag detection, a voltage sag level must be specified in the Voltage Sag Level Register (VSAGLevel), and a voltage sag duration must be specified in the Voltage Sag Duration Register (VSAGDuration). To activate current fault detection, a current sag level must be specified in the Current Fault Level Register (ISAGLevel), and a current sag duration must be specified in the Current Fault Duration Register (ISAGDuration). The voltage and current sag levels are specified as the average of the absolute instantaneous voltage and current, respectively. Voltage and current sag duration is specified in terms of ADC cycles. 5.5.5 PFMON Output Mode Setting bit E3MODE[1:0] = 1 (01b) in the Operational Mode Register outputs the state of the PFMON comparator on pin E3. Figure 8 illustrates the output format with PFMON on E3 E1 E2 E3 Above PFMON Threshold Below PFMON Threshold Figure 8. PFMON output to pin E3 When PFMON is greater then the threshold, pin E3 is high and when PFMON is less than the threshold pin E3 is low. 5.5.6 Design Example EXAMPLE #1: The maximum rated levels for a power line meter are 250 V rms and 20 A rms. The required number of pulses-per-second on E1 is 100 pulses per second (100 Hz), when the levels on the power line are 220 V rms and 15 A rms. With a 10x gain on the voltage and current channel the maximum input signal is 250 mVP. (See Section 5.1 Analog Inputs on page 16.) To prevent over-driving the channel inputs, the maximum rated rms input levels will register 0.6 in VRMS and IRMS by design. Therefore the voltage level at the channel inputs will be 150 mV rms when the maximum rated levels on the power lines are 250 V rms and 20 A rms. Solving for PulseRate using the transfer function: 2 FREQ P × VREFIN PulseRate = -------------------------------------------------------------------------------------------VIN × VGAIN × IIN × IGAIN × PF Level Duration Figure 9. Sag and Fault Detect 5.7 No Load Threshold The No Load Threshold register (LoadMin) is used to disable the active energy pulse output when the magnitude of the PActive register is less than the value in the LoadMin register. Therefore with PF = 1 and: VIN = 220V × ( ( 150mV ) ⁄ ( 250V ) ) = 132mV IIN = 15A × ( ( 150mV ) ⁄ ( 20A ) ) = 112.5mV 5.8 On-chip Temperature Sensor The on-chip temperature sensor is designed to assist in characterizing the measurement element over a desired temperature range. Once a temperature characterization is performed, the temperature sensor can then be utilized to assist in compensating for temperature drift. Temperature measurements are performed during continuous conversions and stored in the Temperature Register. The Temperature Register (T) default is Celsius scale (°C). The Temperature Gain Register (Tgain) and Temperature Offset Register (Toff) are constant values allowing for temperature scale conversions. 19 the pulse rate is: 2 100 × 2.5 PulseRate = ---------------------------------------------------------------- = 420.8754Hz 0.132 × 10 × 0.1125 × 10 and the PulseRateE Register is set to: PulseRateE = --------------------------------------( MCLK ⁄ K ) ⁄ 2048 PulseRate = 0.2104377 with MCLK = 4.096 MHz and K = 1. DS678F2 CS5463 The temperature update rate is a function of the number of ADC samples. With MCLK = 4.096 MHz and K = 1 the update rate is: 2240 samples --------------------------------------- = ( MCLK ⁄ K ) ⁄ 1024 0.56 sec 5.10 System Initialization Upon powering up, the digital circuitry is held in reset until the analog voltage reaches 4.0 V. At that time, an eight-XIN-clock-period delay is enabled to allow the oscillator to stabilize. The CS5463 will then initialize. A hardware reset is initiated when the RESET pin is asserted with a minimum pulse width of 50 ns. The RESET signal is asynchronous, with a Schmitt-trigger input. Once the RESET pin is de-asserted, an eight-XIN-clock-period delay is enabled. A software reset is initiated by writing the command 0x80. After a hardware or software reset, the internal registers (some of which drive output pins) will be reset to their default values. Status bit DRDY in the Status Register, indicates the CS5463 is in its active state and ready to receive commands. The Cycle Count Register (N) must be set to a value greater then one. Status bit TUP in the Status Register, indicates when the Temperature Register is updated. The Temperature Offset Register sets the zero-degree measurement. To improve temperature measurement accuracy, the zero-degree offset may need to be adjusted after the CS5463 is initialized. Temperature-offset calibration is achieved by adjusting the Temperature Offset Register (Toff) by the differential temperature (∆T) measured from a calibrated digital thermometer and the CS5463 temperature sensor. A one-degree adjustment to the Temperature Register (T) is achieved by adding 2.737649x10-4 to the Temperature Offset Register (Toff). Therefore, T off = T off + ( ∆ T × 2.737649 ⋅ 10 –4 ) 5.11 Power-down States The CS5463 has two power-down states, Stand-by and Sleep. In the stand-by state all circuitry except the voltage reference and crystal oscillator is turned off. To return the device to the active state, a power-up command is sent to the device. In Sleep state, all circuitry except the instruction decoder is turned off. When the power-up command is sent to the device, a system initialization is performed (See Section 5.10 System Initialization on page 20). if Toff = -0.0951126 and ∆T = -2.0 (°C), then T off = [ – 0.0951126 + ( – 2.0 × 2.737649 ⋅ 10 –4 ) ] = – 0.09566 or 0xF3C168 (2’s compliment notation) is stored in the Temperature Offset Register (Toff). To convert the Temperature Register (T) from a Celsius scale (°C) to a Fahrenheit scale (°F) utilize the formula o 5.12 Oscillator Characteristics XIN and XOUT are the input and output of an inverting amplifier configured as an on-chip oscillator, as shown in Figure 10. The oscillator circuit is designed to work with a quartz crystal. To reduce circuit cost, two load capacitors C1 and C2 are integrated in the device, from XIN to DGND, and XOUT to DGND. PCB trace lengths should be minimized to reduce stray capacitance. To 9o F = -- ( C + 17.7778 ) 5 Applying the above relationship to the CS5461A temperature measurement algorithm –4 ⎞ o 9 ⎞ T 〈 o C〉 + ⎛ T T 〈 F〉 = ⎛ -- × T ⎝5 ⎝ off + ( 17.7778 × 2.737649 ⋅ 10 )⎠ gain ⎠ XOUT C1 If Toff = -0.09566 and Tgain = 23.507 for a Celsius scale, then the modified values are Toff = -0.09079 (0xF460E1) and Tgain = 42.3132 (0x54A05E) for a Fahrenheit scale. Oscillator Circuit XIN C2 5.9 Voltage Reference The CS5463 is specified for operation with a +2.5 V reference between the VREFIN and AGND pins. To utilize the on-chip 2.5 V reference, connect the VREFOUT pin to the VREFIN pin of the device. The VREFIN can be used to connect external filtering and/or references. DGND C1 = C2 = 22 pF Figure 10. Oscillator Connection DS678F2 20 CS5463 drive the device from an external clock source, XOUT should be left unconnected while XIN is driven by the external circuitry. There is an amplifier between XIN and the digital section which provides CMOS level signals. This amplifier works with sinusoidal inputs so there are no problems with slow edge times. The CS5463 can be driven by an external oscillator ranging from 2.5 to 20 MHz, but the K divider value must be set such that the internal MCLK will run somewhere between 2.5 MHz and 5 MHz. The K divider value is set with the K[3:0] bits in the Configuration Register. As an example, if XIN = MCLK = 15 MHz, and K is set to 5, DCLK will equal 3 MHz, which is a valid value for DCLK. INTERRUPT HANDLER ROUTINE: 4) Read the Status Register. 5) Disable all interrupts. 6) Branch to the proper interrupt service routine. 7) Clear the Status Register by writing back the read value in step 4. 8) Re-enable interrupt 9) Return from interrupt service routine. This handshaking procedure ensures that any new interrupts activated between steps 4 and 7 are not lost (cleared) by step 7. 5.13 Event Handler The INT pin is used to indicate that an internal error or event has taken place in the CS5463. Writing a logic 1 to any bit in the Mask Register allows the corresponding bit in the Status Register to activate the INT pin. The interrupt condition is cleared by writing a logic 1 to the bit that has been set in the Status Register. The behavior of the INT pin is controlled by the IMODE and IINV bits of the Configuration Register. IMODE IINV INT Pin 5.14 Serial Port Overview The CS5463 incorporates a serial port transmit and receive buffer with a command decoder that interprets one-byte (8-bit) commands as they are received. There are four types of commands: instructions, synchronizing, register writes, and register reads (See Section 5.16 Commands on page 23). Instructions are one byte in length and will interrupt any instruction currently executing. Instructions do not affect register reads currently being transmitted. Synchronizing commands are one byte in length and only affect the serial interface. Synchronizing commands do not affect operations currently in progress. Register writes must be followed by three bytes of data. Register reads can return up to four bytes of data. Commands and data are transferred most-significant bit (MSB) first. Figure 1 on page 12, defines the serial port timing and required sequence necessary for writing to and reading from the serial port receive and transmit buffer, respectively. While reading data from the serial port, commands and data can be written simultaneously. Starting a new register read command while data is being read will terminate the current read in progress. This is acceptable if the remainder of the current read data is not needed. During data reads, the serial port requires input data. If a new command and data is not sent, SYNC0 or SYNC1 must be sent. 0 0 1 1 0 1 0 1 Active-low Level Active-high Level Low Pulse High Pulse Table 4. Interrupt Configuration If the interrupt output signal format is set for either falling or rising edge, the duration of the INT pulse will be at least one DCLK cycle (DCLK = MCLK/K). 5.13.1 Typical Interrupt Handler The steps below show how interrupts can be handled. INITIALIZATION: 1) All Status bits are cleared by writing 0xFFFFFF to the Status Register. 2) The condition bits which will be used to generate interrupts are then set to logic 1 in the Mask Register. 3) Enable interrupts. 5.14.1 Serial Port Interface The serial port interface is a “4-wire” synchronous serial communications interface. The interface is enabled to start excepting SCLKs when CS (Chip Select) is asserted (logic 0). SCLK (Serial bit-clock) is a Schmitt-trigger input that is used to strobe the data on SDI (Serial Data In) into the receive buffer and out of the transmit buffer onto SDO (Serial Data Out). DS678F2 21 CS5463 If the serial port interface becomes unsynchronized with respect to the SCLK input, any attempt to clock valid commands into the serial interface may result in unexpected operation. Therefor, the serial port interface must then be re-initialized by one of the following actions: Drive the CS pin high, then low. Hardware Reset (drive RESET pin low for at least 10 µs). Issue the Serial Port Initialization Sequence, which is 3 (or more) SYNC1 command bytes (0xFF) followed by one SYNC0 command byte (0xFE). 0x800 0x7FF Hardware Registers* 32 Pages 0x400 0x3FF Software Register* 32 Pages 0x000 * Accessed using register read/write commands. Pages 0 - 0x1F Pages 0x20 - 0x3F registers in another page, the Page Register (address 0x1F) must be written with the desired page number. 0xFFF ROM 2048 Words Pages 0x40 - 0x7F If a re-synchronization is necessary, it is best to re-initialize the part either by hardware or software reset (command 0x80), as the state of the part may be unknown. 5.15 Register Paging Read/write commands access one of the 32 registers within a specified page. By default, Page = 0. To access Figure 11. CS5463 Memory Map Example: Reading register 6 in page 3. 1. Write 3 to page register with command and data: 0x7E 0x00 0x00 0x03 2. Read register 6 with command: 0x0C 0xFF 0xFF 0xFF 22 DS678F2 CS5463 5.16 Commands All commands are 8 bits in length. Any command byte value that is not listed in this section is invalid. Commands that write to registers must be followed by 3 bytes of data. Commands that read data can be chained with other commands (e.g., while reading data, a new command can be sent which can execute during the original read). All commands except register reads, register writes, and SYNC0 & SYNC1 will abort any currently executing commands. 5.16.1 Start Conversions B7 1 B6 1 B5 1 B4 0 B3 C3 B2 0 B1 0 B0 0 Initiates acquiring measurements and calculating results. The device has two modes of acquisition. C3 Modes of acquisition/measurement 0 = Perform a single computation cycle 1 = Perform continuous computation cycles 5.16.2 SYNC0 and SYNC1 B7 1 B6 1 B5 1 B4 1 B3 1 B2 1 B1 1 B0 SYNC The serial port can be initialized by asserting CS or by sending three or more consecutive SYNC1 commands followed by a SYNC0 command. The SYNC0 or SYNC1 can also be sent while sending data out. SYNC 0 = Last byte of a serial port re-initialization sequence. 1 = Used during reads and serial port initialization. 5.16.3 Power-up/Halt B7 1 B6 0 B5 1 B4 0 B3 0 B2 0 B1 0 B0 0 If the device is powered-down, Power-Up/Halt will initiate a power on reset. If the part is already powered-on, all computations will be halted. 5.16.4 Power-down and Software Reset B7 1 B6 0 B5 0 B4 S1 B3 S0 B2 0 B1 0 B0 0 To conserve power the CS5463 has two power-down states. In stand-by state all circuitry, except the analog/digital clock generators, is turned off. In the sleep state all circuitry, except the command decoder, is turned off. Bringing the CS5463 out of sleep state requires more time than out of stand-by state, because of the extra time needed to re-start and re-stabilize the analog oscillator. S[1:0] Power-down state 00 = Software Reset 01 = Halt and enter stand-by power saving state. This state allows quick power-on 10 = Halt and enter sleep power saving state. 11 = Reserved DS678F2 23 CS5463 5.16.5 Register Read/Write B7 0 B6 W/R B5 RA4 B4 RA3 B3 RA2 B2 RA1 B1 RA0 B0 0 The Read/Write informs the command decoder that a register access is required. During a read operation, the addressed register is loaded into an output buffer and clocked out by SCLK. During a write operation, the data is clocked into an input buffer and transferred to the addressed register upon completion of the 24th SCLK. W/R Write/Read control 0 = Read 1 = Write Register address bits (bits 5 through 1) of the read/write command. RA[4:0] Register Page 0 Address 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 RA[4:0] 00000 00001 00010 00011 00100 00101 00110 00111 01000 01001 01010 01011 01100 01101 01110 01111 10000 10001 10010 10011 10100 10101 10110 10111 11000 11001 11010 11011 11100 11101 11110 11111 Name Config IDCoff Ign VDCoff Vgn Cycle Count PulseRateE I V P PActive IRMS VRMS ε (Epsilon) Poff Status IACoff VACoff Mode T QAVG Q IPeak VPeak QTrig PF Mask S Ctrl PH PF QF Description Configuration Current DC Offset Current Gain Voltage DC Offset Voltage Gain Number of A/D conversions used in one computation cycle (N)). Sets the E1, E2 and E3 energy-to-frequency output pulse rate. Instantaneous Current Instantaneous Voltage Instantaneous Power Active (Real) Power RMS Current RMS Voltage Ratio of line frequency to output word rate (OWR) Power Offset Status Current AC (RMS) Offset Voltage AC (RMS) Offset Operation Mode Temperature Average Reactive Power Instantaneous Reactive Power Peak Current Peak Voltage Reactive Power calculated from Power Triangle Power Factor Interrupt Mask Apparent Power Control Harmonic Active Power Fundamental Active Power Fundamental Reactive Power / Page Note: For proper operation, do not attempt to write to unspecified registers. 24 DS678F2 CS5463 Register Page 1 Address 0 1 2 3 RA[4:0] 00000 00001 00010 00011 Name PulseWidth LoadMin TGain Toff Description Energy Pulse Output Width No Load Threshold Temperature Sensor Gain Temperature Sensor Offset Register Page 3 Address 6 7 10 11 RA[4:0] 00110 00111 01010 01011 Name VSAGDuration VSAGLevel ISAGDuration ISAGLevel Description Voltage sag sample interval Voltage sag level Current fault sample interval Current fault level Note: For proper operation, do not attempt to write to unspecified registers. 5.16.6 Calibration B7 1 B6 1 B5 0 B4 CAL4 B3 CAL3 B2 CAL2 B1 CAL1 B0 CAL0 The CS5463 can perform system calibrations. Proper input signals must be applied to the current and voltage channel before performing a designated calibration. CAL[4:0]* Designates calibration to be performed 01001 = Current channel DC offset 01010 = Current channel DC gain 01101 = Current channel AC offset 01110 = Current channel AC gain 10001 = Voltage channel DC offset 10010 = Voltage channel DC gain 10101 = Voltage channel AC offset 10110 = Voltage channel AC gain 11001 = Current and Voltage channel DC offset 11010 = Current and Voltage channel DC gain 11101 = Current and Voltage channel AC offset 11110 = Current and Voltage channel AC gain *For proper operation, values for CAL[4:0] not specified should not be used. DS678F2 25 CS5463 6. REGISTER DESCRIPTION 1. 2. “Default” = bit status after power-on or reset Any bit not labeled is Reserved. A zero should always be used when writing to one of these bits. 6.1 Page 0 Registers 6.1.1 Configuration Register ( Config ) Address: 0 23 PC6 15 EWA 7 22 PC5 14 6 21 PC4 13 5 20 PC3 12 IMODE 4 iCPU 19 PC2 11 IINV 3 K3 18 PC1 10 2 K2 17 PC0 9 1 K1 16 Igain 8 0 K0 Default = 0x000001 PC[6:0] Phase compensation. A 2’s complement number which sets a delay in the voltage channel relative to the current channel. Default setting is 0000000 = 0.0215 degree phase delay at 60 Hz (when MCLK = 4.096 MHz). See Section 7.2 Phase Compensation on page 39 for more information. Sets the gain of the current PGA. 0 = Gain is 10 (default) 1 = Gain is 50 Allows the E1 and E2 pins to be configured as open-collector output pins. 0 = Normal outputs (default) 1 = Only the pull-down device of the E1 and E2 pins are active Interrupt configuration bits. Select the desired pin behavior for indication of an interrupt. 00 = Active-low level (default) 01 = Active-high level 10 = High-to-low pulse 11 = Low-to-high pulse Inverts the CPUCLK clock. In order to reduce the level of noise present when analog signals are sampled, the logic driven by CPUCLK should not be active during the sample edge. 0 = Normal operation (default) 1 = Minimize noise when CPUCLK is driving rising edge logic Clock divider. A 4-bit binary number used to divide the value of MCLK to generate the internal clock DCLK. The internal clock frequency is DCLK = MCLK/K. The value of K can range between 1 and 16. Note that a value of “0000” will set K to 16 (not zero). K = 1 at reset. Igain EWA IMODE, IINV iCPU K[3:0] 26 DS678F2 CS5463 6.1.2 Current and Voltage DC Offset Register ( IDCoff , VDCoff ) Address: 1 (Current DC Offset); 3 (Voltage DC Offset) MSB -(2 ) 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 Default = 0x000000 The DC Offset registers (IDCoff,VDCoff) are initialized to 0.0 on reset. When DC Offset calibration is performed, the register is updated with the DC offset measured over a computation cycle. DRDY will be set at the end of the calibration. This register may be read and stored for future system offset compensation. The value is represented in two's complement notation and in the range of -1.0 ≤ IDCoff, VDCoff < 1.0, with the binary point to the right of the MSB. See Section 7.1.2.1 DC Offset Calibration Sequence on page 37 for more information. 6.1.3 Current and Voltage Gain Register ( Ign , Vgn ) Address: 2 (Current Gain); 4 (Voltage Gain) MSB 21 20 2-1 2-2 2-3 2-4 2-5 2-6 ..... 2-16 2-17 2-18 2-19 2-20 2-21 LSB 2-22 Default = 0x400000 = 1.000 The gain registers (Ign,Vgn) are initialized to 1.0 on reset. When either a AC or DC Gain calibration is performed, the register is updated with the gain measured over a computation cycle. DRDY will be set at the end of the calibration. This register may be read and stored for future system gain compensation. The value is in the range 0.0 ≤ Ign,Vgn < 3.9999, with the binary point to the right of the second MSB. 6.1.4 Cycle Count Register ( Cycle Count ) Address: 5 MSB 223 222 221 220 219 218 217 216 ..... 26 25 24 23 22 21 LSB 20 Default = 0x000FA0 = 4000 Cycle Count, denoted as N, determines the length of one computation cycle. During continuous conversions, the computation cycle frequency is (MCLK/K)/(1024∗N). A one second computational cycle period occurs when MCLK = 4.096 MHz, K = 1, and N = 4000. 6.1.5 PulseRateE Register ( PulseRateE ) Address: 6 MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 Default = 0x800000 = 1.00 (2 kHz @ 4.096 MHz MCLK) PulseRateE sets the frequency of E1, E2, & E3 pulses. E1, E2, E3 frequency = (MCLK x PulseRateE) / 2048 at full scale. For a 4 khz sample rate, the maximum pulse rate is 2 khz. The value is represented in two's complement notation and in the range is -1.0 ≤ PulseRateE < 1.0, with the binary point to the right of the MSB. Negative values have the same effect as positive. See Section 5.5 Energy Pulse Output on page 17 for more information. DS678F2 27 CS5463 6.1.6 Instantaneous Current, Voltage, and Power Registers ( I , V , P ) Address: 7 (Instantaneous Current); 8 (Instantaneous Voltage); 9 (Instantaneous Power) MSB -(2 ) 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 I and V contain the instantaneous measured values for current and voltage, respectively. The instantaneous voltage and current samples are multiplied to obtain Instantaneous Power (P). The value is represented in two's complement notation and in the range of -1.0 ≤ I, V, P < 1.0, with the binary point to the right of the MSB. 6.1.7 Active (Real) Power Register ( PActive ) Address: 10 (Active Power) MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 The instantaneous power is averaged over each computation cycle (N conversions) to compute Active Power (PActive). The value will be within in the range of -1.0 ≤ PActive< 1.0. The value is represented in two's complement notation, with the binary point to the right of the MSB. 6.1.8 RMS Current & Voltage Registers ( IRMS , VRMS ) Address: 11 (IRMS); 12 (VRMS) MSB 2-1 2-2 2-3 2-4 2-5 2-6 2-7 2-8 ..... 2-18 2-19 2-20 2-21 2-22 2-23 LSB 2-24 IRMS and VRMS contain the Root Mean Square (RMS) values of I and V, calculated each computation cycle. The value is represented in unsigned binary notation and in the range of 0.0 ≤ IRMS, VRMS < 1.0, with the binary point to the left of the MSB. 6.1.9 Epsilon Register ( ε ) Address: 13 MSB -(2 0) LSB 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 2-23 Default = 0x01999A = 0.0125 sec Epsilon (ε) is the ratio of the input line frequency to the sample frequency of the ADC (See Section 5.4 Performing Measurements on page 16). Epsilon is either written to the register, or measured during conversions. The value is represented in two's complement notation and in the range of -1.0 ≤ ε < 1.0, with the binary point to the right of the MSB. Negative values have no significance. 28 DS678F2 CS5463 6.1.10 Power Offset Register ( Poff ) Address: 14 MSB -(2 ) 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 Default = 0x000000 Power Offset (Poff) is added to the instantaneous power being accumulated in the Pactive register, and can be used to offset contributions to the energy result that are caused by undesirable sources of energy that are inherent in the system. The value is represented in two's complement notation and in the range of -1.0 ≤ Poff < 1.0, with the binary point to the right of the MSB. 6.1.11 Status Register and Mask Register ( Status , Mask ) Address: 15 (Status Register); 26 (Mask Register) 23 DRDY 15 7 TUP 22 14 IROR 6 TOD 21 13 VROR 5 20 CRDY 12 EOR 4 VOD 19 11 IFAULT 3 IOD 18 10 VSAG 2 LSD 17 IOR 9 1 FUP 16 VOR 8 0 IC Default = 0x800001 (Status Register), 0x000000 (Mask Register) The Status Register indicates status within the chip. In normal operation, writing a '1' to a bit will cause the bit to reset. Writing a '0' to a bit will not change it’s current state. The Mask Register is used to control the activation of the INT pin. Placing a logic '1' in a Mask bit will allow the corresponding bit in the Status Register to activate the INT pin when the status bit is asserted. DRDY CRDY IOR VOR IROR VROR EOR IFAULT VSAG TUP TOD VOD (IOD) DS678F2 Data Ready. During conversions, this bit will indicate the end of computation cycles. For calibrations, this bit indicates the end of a calibration sequence. Conversion Ready. Indicates a new conversion is ready. This will occur at the output word rate. Current Out of Range. Set when the Instantaneous Current Register overflows. Voltage Out of Range. Set when the Instantaneous Voltage Register overflows. IRMS Out of Range. Set when the IRMS Register overflows. VRMS Out of Range. Set when the VRMS Register overflows. Energy Out of Range. Set when PACTIVE overflows. Indicates a current fault has occurred. See Section 5.6 Sag and Fault Detect Feature on page 19. Indicates a voltage sag has occurred. See Section 5.6 Sag and Fault Detect Feature on page 19. Temperature Updated. Indicates the Temperature Register has updated. Modulator oscillation detected on the temperature channel. Set when the modulator oscillates due to an input above full scale. Modulator oscillation detected on the voltage (current) channel. Set when the modulator oscil29 CS5463 lates due to an input above full scale. The level at which the modulator oscillates is significantly higher than the voltage channel’s differential input voltage (current) range. Note: The IOD and VOD bits may be ‘falsely’ triggered by very brief voltage spikes from the power line. This event should not be confused with a DC overload situation at the inputs, when the IOD and VOD bits will re-assert themselves even after being cleared, multiple times. LSD Low Supply Detect. Set when the voltage at the PFMON pin falls below the low-voltage threshold (PMLO), with respect to AGND pin. The LSD bit cannot be reset until the voltage at PFMON pin rises back above the high-voltage threshold (PMHI). Epsilon Updated. Indicates completion of a line frequency measurement and update of Epsilon. Invalid Command. Normally logic 1. Set to logic 0 if an invalid command is received or the Status Register has not been successfully read. FUP IC 6.1.12 Current and Voltage AC Offset Register ( VACoff , IACoff ) Address: 16 (Current AC Offset); 17 (Voltage AC Offset) MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 Default = 0x000000 The AC Offset Registers (VACoff, IACoff) are initialized to zero on reset, allowing for uncalibrated normal operation. AC Offset Calibration updates these registers. This sequence lasts approximately (6N + 30) ADC cycles (where N is the value of the Cycle Count Register). DRDY will be asserted at the end of the calibration. These values may be read and stored for future system AC offset compensation. The value is represented in two's complement notation in the range of -1.0 ≤ VACoff, IACoff < 1.0, with the binary point to the right of the MSB 6.1.13 Operational Mode Register ( Mode ) Address: 18 23 15 7 XIDEL 22 14 6 IHPF 21 13 5 VHPF 20 12 4 IIR 19 11 3 E3MODE1 18 10 2 E3MODE0 17 9 E2MODE 1 POS 16 8 XVDEL 0 AFC Default = 0x000000 E2MODE E2 Output Mode 0 = Energy Sign (default) 1 = Apparent Power Enables an extra sample of voltage channel delay. XVDEL and XIDEL can not be enabled at the same time. Enables an extra sample of current channel delay. XVDEL and XIDEL can not be enabled at the same time. XVDEL XIDEL 30 DS678F2 CS5463 IHPF (VHPF) Enables the high-pass filter on the current (voltage) channel. 0 = High-pass filter disabled (default) 1 = High-pass filter enabled Note: When either IHPF or VHPF are enabled, but not both, an all-pass filter is applied to the opposite channel for phase matching. IIR Enables the IIR compensation filters. 0 = IIR compensation filters enabled (default) 1 = IIR compensation filters disabled E3 Output Mode 00 = Reactive Power (default) 01 = PFMON 10 = Voltage sign 11 = Apparent Power Positive Energy Only. Negative energy pulses on E1 are suppressed. However, it will NOT suppress negative P Register results. Enables automatic line-frequency measurement and sets the frequency of the local sine/cosine generator used in fundamental/harmonic measurements. When AFC is enabled, the Epsilon register will be updated periodically. E3MODE[1:0] POS AFC 6.1.14 Temperature Register ( T ) Address: 19 MSB -(27) 26 25 24 23 22 21 20 ..... 2-10 2-11 2-12 2-13 2-14 2-15 LSB 2-16 T contains measurements from the on-chip temperature sensor. Measurements are performed during continuous conversions, with the default the Celsius scale (oC). The value is represented in two's complement notation and in the range of -128.0 ≤ T < 128.0, with the binary point to the right of the eighth MSB. 6.1.15 Average and Instantaneous Reactive Power Register ( QAVG , Q ) Address: 20 (Average Reactive Power) and 21 (Instantaneous Reactive Power) MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 The Instantaneous Reactive Power (Q) is the product of the voltage, shifted 90 degrees, and the current. The Average Reactive Power (QAVG) is Q averaged over N samples. The results are signed values with. The value is represented in two's complement notation and in the range of -1.0 < Q, QAVG< 1.0, with the binary point to the right of the MSB. 6.1.16 Peak Current and Peak Voltage Register ( Ipeak , Vpeak ) Address: 22 (Peak Currect) and 23 (Peak Voltage) MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 The Peak Current (Ipeak) and Peak Voltage (Vpeak) registers contain the instantaneous current and voltage with the greatest magnitude detected during the last computation cycle. The value is represented in two's complement notation and in the range of -1.0 ≤ Ipeak, Vpeak < 1.0, with the binary point to the right of the MSB. DS678F2 31 CS5463 6.1.17 Reactive Power Register ( QTrig ) Address: 24 MSB 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 The Reactive Power (QTrig) is calculated using trigonometric identities. (See Section 4.3 Power Measurements on page 14). The value is represented in unsigned notation and in the range of 0 ≤ S < 1.0, with the binary point to the right of the MSB. 6.1.18 Power Factor Register ( PF ) Address: 25 MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 Power Factor is calculated by dividing the Active (Real) Power by Apparent Power. The value is represented in two's complement notation and in the range of -1.0 ≤ PF < 1.0, with the binary point to the right of the MSB. 6.1.19 Apparent Power Register ( S ) Address: 27 MSB 0 LSB 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 2-23 Apparent power (S) is the product of the VRMS and IRMS, The value is represented in unsigned notation and in the range of 0 ≤ S < 1.0, with the binary point to the right of the MSB. 32 DS678F2 CS5463 6.1.20 Control Register ( Ctrl ) Register Address: 28 23 15 7 22 14 6 21 13 5 20 12 4 INTOD 19 11 3 18 10 2 NOCPU 17 9 1 NOOSC 16 8 STOP 0 Default = 0x000000 STOP Terminates the auto-boot sequence. 0 = Normal (default) 1 = Stop sequence Converts INT output pin to an open drain output. 0 = Normal (default) 1 = Open drain Saves power by disabling the CPUCLK pin. 0 = Normal (default) 1 = Disables CPUCLK Saves power by disabling the crystal oscillator. 0 = Normal (default) 1 = Disabling oscillator circuit INTOD NOCPU NOOSC 6.1.21 Harmonic Active Power Register ( PH ) Address: 29 MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 The Harmonic Active Power (PH) is calculated by subtracting the Fundamental Active Power from the Active (Real) Power. The value is represented in two's complement notation and in the range of -1.0 ≤ PH < 1.0, with the binary point to the right of the MSB. 6.1.22 Fundamental Active Power Register ( PF ) Address: 30 MSB -(2 ) 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 The Fundamental Active Power (PF) is calculated by performing a discrete Fourier transform (DFT) at the relevant frequency on the V and I channels. The results are multiplied to yield fundamental power. The value is represented in two's complement notation and in the range of -1.0 ≤ PH < 1.0, with the binary point to the right of the MSB. DS678F2 33 CS5463 6.1.23 Fundamental Reactive Power Register ( QH ) Address: 31 (read only) MSB -(2 ) 0 LSB 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 Fundamental Reactive Power (QH) is calculated by performing a discrete Fourier transform (DFT) at the relevant frequency on the V and I channels. The value is represented in two's complement notation and in the range of -1.0 ≤ QH < 1.0, with the binary point to the right of the MSB. 6.1.24 Page Register Address: 31 (write only) MSB 26 25 24 23 22 21 LSB 20 Default = 0x00 Determines which register page the serial port will access. 34 DS678F2 CS5463 6.2 Page 1 Registers 6.2.1 Energy Pulse Output Width ( PulseWidth ) Address: 0 MSB 0 222 221 220 219 218 217 216 ..... 26 25 24 23 22 21 LSB 20 Default = 1 PulseWidth sets the duration of energy pulses (tPW). The actual pulse duration is the contents of PulseWidth divided by the output word rate (OWR). PulseWidth is an integer in the range of 1 to 8388607. 6.2.2 No Load Threshold ( LoadMin ) Address: 1 MSB -(20) 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 Default = 0 LoadMin is used to set the no load threshold. When the magnitude of the PActive register is less than LoadMin, the active energy pulse output will be disabled. LoadMin is a two's complement value in the range of -1.0 ≤ LoadMin < 1.0, with the binary point to the right of the MSB. Negative values are not used. 6.2.3 Temperature Gain Register ( TGain ) Address: 2 MSB 26 25 24 23 22 21 20 2-1 ..... 2-11 2-12 2-13 2-14 2-15 2-16 LSB 2-17 Default = 0x2F03C3 = 23.5073471 Sets the temperature channel gain. Temperature gain (TGain) is utilized to convert from one temperature scale to another. The Celsius scale (oC) is the default. Values will be within in the range of 0 ≤ TGain < 128. The value is represented in unsigned notation, with the binary point to the right of bit 7th MSB. See Section 5.8 On-chip Temperature Sensor on page 19. 6.2.4 Temperature Offset Register ( TOff ) Address: 3 MSB -(20 ) 2 -1 LSB 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2-17 2 -18 2 -19 2 -20 2 -21 2 -22 2-23 Default = 0xF3D35A = -0.0951126 Temperature offset (Toff) is used to remove the temperature channel’s offset at the zero-degree reading. Values are represented in two's complement notation and in the range of -1.0 ≤ Toff < 1.0, with the binary point to the right of the MSB. DS678F2 35 CS5463 6.3 Page 3 Registers 6.3.1 Voltage Sag and Current Fault Duration Registers ( VSAGDuration , ISAGDuration ) Address: 6 (Voltage Sag Duration); 10 (Current Fault Duration) MSB 0 LSB 222 221 220 219 218 217 216 ..... 26 25 24 23 22 21 20 Default = 0x000000 Voltage Sag Duration (VSAGDuration) and Current Fault Duration (ISAGDuration) defines the number of instantaneous measurements utilized to determine a sag event. Setting these register to zero will disable this feature. The value is represented in unsigned notation. See Section 5.6 Sag and Fault Detect Feature on page 19. 6.3.2 Voltage Sag and Current Fault Level Registers ( VSAGLevel , ISAGLevel ) Address: 7 (Voltage Sag Level ); 11 (Current Fault Level ) MSB 0 2-1 2-2 2-3 2-4 2-5 2-6 2-7 ..... 2-17 2-18 2-19 2-20 2-21 2-22 LSB 2-23 Default = 0x000000 Voltage Sag Level (VSAGLevel) and Current Fault Level (ISAGLevel) defines the voltage level that the magnitude of input samples, averaged over the sag duration, must fall below in order to register a sag/fault condition. These value are represented in unsigned notation and in the range of 0 ≤ VSAGLevel < 1.0, with the binary point to the right of the third MSB. See Section 5.6 Sag and Fault Detect Feature on page 19. 36 DS678F2 CS5463 7. SYSTEM CALIBRATION 7.1 Channel Offset and Gain Calibration The CS5463 provides digital DC offset and gain compensation that can be applied to the instantaneous voltage and current measurements, and AC offset compensation to the voltage and current RMS calculations. Since the voltage and current channels have independent offset and gain registers, system offset and/or gain can be performed on either channel without the calibration results from one channel affecting the other. The computational flow of the calibration sequences are illustrated in Figure 12. The flow applies to both the voltage channel and current channel. N + 30 conversion cycles to complete. For AC offset calibrations, the sequence takes at least 6N + 30 ADC cycles to complete, (about 6 computation cycles). As N is increased, the accuracy of calibration results will increase. 7.1.2 Offset Calibration Sequence For DC and AC offset calibrations, the VIN± pins of the voltage and IIN± pins of the current channels should be connected to their ground reference level. (see Figure 13.) External Connections + AIN+ 0V + CM + AINXGAIN + 7.1.1 Calibration Sequence The CS5463 must be operating in its active state and ready to accept valid commands. Refer to Section 5.16 Commands on page 23. The calibration algorithms are dependent on the value N in the Cycle Count Register (see Figure 12). Upon completion, the results of the calibration are available in their corresponding register. The DRDY bit in the Status Register will be set. If the DRDY bit is to be output on the INT pin, then DRDY bit in the Mask Register must be set. The initial values in the AC gain and offset registers do affect the results of the calibration results. Figure 13. System Calibration of Offset The AC offset registers must be set to the default (0x000000). 7.1.2.1 DC Offset Calibration Sequence Channel gain should be set to 1.0 when performing DC offset calibration. Initiate a DC offset calibration. The DC offset registers are updated with the negative of the average of the instantaneous samples collected over a computational cycle. Upon completion of the DC offset calibration the DC offset is stored in the corresponding DC offset register. The DC offset value will be added to to V*, I* Registers 7.1.1.1 Duration of Calibration Sequence The value of the Cycle Count Register (N) determines the number of conversions performed by the CS5463 during a given calibration sequence. For DC offset and gain calibrations, the calibration sequence takes at least In Modulator Filter + + + X X Σ N ÷N √ + + + VRMS*, IRMS* Registers DC Offset* Gain* Σ N AC Offset* Inverse ÷N -1 X -1 X 0.6 RMS * Denotes readable/writable register Figure 12. Calibration Data Flow DS678F2 37 CS5463 each instantaneous measurement to nullify the DC component present in the system during conversion commands. A typical rms calibration value which allows for reasonable over-range margin would be 0.6 or 60% of the voltage and current channel’s maximum input voltage level. Two examples of AC gain calibration and the updated digital output codes of the channel’s instantaneous data registers are shown in Figures 15 and 16. Figure 16 Before AC Gain Calibration (Vgn Register = 1) 250 mV Sinewave 7.1.2.2 AC Offset Calibration Sequence Corresponding offset registers IACoff and/or VACoff should be cleared prior to initiating AC offset calibrations. Initiate an AC offset calibration.The AC offset registers are updated with an offset value that reflects the RMS output level. Upon completion of the AC offset calibration the AC offset is stored in the corresponding AC offset register. The AC offset register value is subtracted from each successive VRMS and IRMS calculation. 0.9999... 0.92 Instantaneous Voltage Register Values -0.92 -1.0000... 230 mV INPUT 0V SIGNAL -230 mV -250 mV 7.1.3 Gain Calibration Sequence When performing gain calibrations, a reference signal should be applied to the VIN± pins of the voltage and IIN± pins of the current channels that represents the desired maximum signal level. Figure 14 shows the basic setup for gain calibration. External Connections R eference + Signal - VRMS Register = 230/√2 x 1/250 ≈ 0.65054 After AC Gain Calibration (Vgn Register changed to approx. 0.9223) 250 mV Sinewave 0.92231 0.84853 Instantaneous Voltage Register Values -0.84853 -0.92231 230 mV INPUT 0V SIGNAL -230 mV IN+ + XG AIN + - -250 mV VRMS Register = 0.600000 CM Figure 15. Example of AC Gain Calibration + - IN- Before AC Gain Calibration (Vgain Register = 1) Figure 14. System Calibration of Gain. 250 mV 230 mV DC Signal 0.9999... 0.92 Instantaneous Voltage Register Values For gain calibrations, there is an absolute limit on the RMS voltage levels that are selected for the gain calibration input signals. The maximum value that the gain registers can attain is 4. Therefore, if the signal level of the applied input is low enough that it causes the CS5463 to attempt to set either gain register higher than 4, the gain calibration result will be invalid and all CS5463 results obtained while performing measurements will be invalid. If the channel gain registers are initially set to a gain other then 1.0, AC gain calibration should be used. INPUT 0 V SIGNAL -250 mV 230 VRMS Register = 250 = 0.92 -1.0000... After AC Gain Calibration (Vgain Register changed to approx. 0.65217) 250 mV 230 mV DC Signal 0.65217 0.6000 Instantaneous Voltage Register Values 7.1.3.1 AC Gain Calibration Sequence The corresponding gain register should be set to 1.0, unless a different initial gain value is desired. Initiate an AC gain calibration. The AC gain calibration algorithm computes the RMS value of the reference signal applied to the channel inputs. The RMS register value is then divided into 0.6 and the quotient is stored in the corresponding gain register. Each instantaneous measurement will be multiplied by its corresponding AC gain value. 38 INPUT 0V SIGNAL -250 mV -0.65217 VRMS Register = 0.600000 Figure 16. Example of AC Gain Calibration shows that a positive (or negative) DC-level signal can be used even though an AC gain calibration is being executed. DS678F2 CS5463 However, an AC signal cannot be used for DC gain calibration. culated in step 2 by the gain calculated in step 3 and updating the AC offset register with the product. 7.1.3.2 DC Gain Calibration Sequence Initiate a DC gain calibration. The corresponding gain register is restored to default (1.0). The DC gain calibration averages the channel’s instantaneous measurements over one computation cycle (N samples). The average is then divided into 1.0 and the quotient is stored in the corresponding gain register After the DC gain calibration, the instantaneous register will read at full-scale whenever the DC level of the input signal is equal to the level of the DC calibration signal applied to the inputs during the DC gain calibration.The HPF option should not be enabled if DC gain calibration is utilized. 7.2 Phase Compensation The CS5463 is equipped with phase compensation to cancel out phase shifts introduced by the measurement element. Phase Compensation is set by bits PC[6:0] in the Configuration Register and bits XVDEL and XIDEL in the Operational Mode Register The default value of PC[6:0], XVDEL, and XIDEL is zero. With MCLK = 4.096 MHz and K = 1, the phase compensation has a range of ±8.1 degrees when the input signals are 60 Hz. Under these conditions, each step of the phase compensation register (value of one LSB) is approximately 0.04 degrees. For values of MCLK other than 4.096 MHz, the range and step size should be scaled by 4.096 MHz/(MCLK/K). For power line frequencies other than 60Hz, the values of the range and step size of the PC[6:0] bits can be determined by converting the above values from angular measurement into the time domain (seconds), and then computing the new range and step size (in degrees) with respect to the new line frequency. To calculate the phase shift induced between the voltage and the current channel use the equation: o Freq × 360 × ( PC [ 5:0 ] – ( PC [ 6 ] × 64 ) + ( XDEL × 128 ) ) = --------------------------------------------------------------------------------------------------------------------------------( MCLK ⁄ K ) ⁄ 8 7.1.4 Order of Calibration Sequences 1. If the HPF option is enabled, then any DC component that may be present in the selected signal path will be removed and a DC offset calibration is not required. However, if the HPF option is disabled the DC offset calibration sequence should be performed. When using high-pass filters, it is recommended that the DC Offset register for the corresponding channel be set to zero. When performing DC offset calibration, the corresponding gain channel should be set to one. 2. If there is an AC offset in the VRMS or IRMS calculation, then the AC offset calibration sequence should be performed. 3. Perform the gain calibration sequence. 4. Finally, if an AC offset calibration was performed (step 2), then the AC offset may need to be adjusted to compensate for the change in gain (step 3). This can be accomplished by restoring zero to the AC offset register and then perform an AC offset calibration sequence. The adjustment could also be done by multiplying the AC offset register value that was cal- Phase Freq = Line Frequency [Hz] XDEL = XVDEL or -XIDEL 7.3 Active Power Offset The Power Offset Register can be used to offset system power sources that may be resident in the system, but do not originate from the power line signal. These sources of extra energy in the system contribute undesirable and false offsets to the power and energy measurement results. After determining the amount of stray power, the Power Offset Register can be set to cancel the effects of this unwanted energy. DS678F2 39 CS5463 8. AUTO-BOOT MODE USING E2PROM When the CS5463 MODE pin is asserted (logic 1), the CS5463 auto-boot mode is enabled. In auto-boot mode, the CS5463 downloads the required commands and register data from an external serial E2PROM, allowing the CS5463 to begin performing energy measurements. commands/data will determine the CS5463’s exact operation, when the auto-boot initialization sequence is running. Any of the valid commands can be used. 8.2 Auto-boot Data for E2PROM Below is an example code set for an auto-boot sequence. This code is written into the E2PROM by the user. The serial data for such a sequence is shown below in single-byte hexidecimal notation: -64 00 00 60 Write Operation Mode Register, turn high-pass filters on. -44 7F C4 A9 Write value of 0x7FC4A9 to Current Gain Register. -48 FF B2 53 Write value of 0xFFB253 to Voltage Gain Register. -74 00 00 04 Unmask bit #2 (LSD) in the Mask Register. -E8 Start continuous conversions -78 00 01 00 Write STOP bit to Control Register, to terminate auto-boot initialization sequence. 8.1 Auto-boot Configuration A typical auto-boot serial connection between the CS5463 and a E2PROM is illustrated in Figure 17. In auto-boot mode, the CS5463’s CS and SCLK are configured as outputs. The CS5463 asserts CS (logic 0), provides a clock on SCLK, and sends a read command to the E2PROM on SDO. The CS5463 reads the user-specified commands and register data presented on the SDI pin. The E2PROM’s programmed data is utilized by the CS5463 to change the designated registers’ default values and begin registering energy. VD+ EOUT1 EOUT2 5K Mech. Counter or Stepper Motor CS5463 SCLK SDI SDO MODE CS 5K EEPROM SCK SO SI CS 8.3 Which E2PROMs Can Be Used? Connector to Calibrator Several industry-standard serial E2PROMs that will successfully run auto-boot with the CS5461A are listed below: • • • Atmel AT25010, AT25020 or AT25040 National Semiconductor NM25C040M8 or NM25020M8 Xicor X25040SI Figure 17. Typical Interface of E2PROM to CS5463 Figure 17 also shows the external connections that would be made to a calibrator device, such as a PC or custom calibration board. When the metering system is installed, the calibrator would be used to control calibration and/or to program user-specified commands and calibration values into the E2PROM. The user-specified These types of serial E2PROMs expect a specific 8-bit command (00000011) in order to perform a memory read. The CS5461A has been hardware programmed to transmit this 8-bit command to the E2PROM at the beginning of the auto-boot sequence. 40 DS678F2 CS5463 9. BASIC APPLICATION CIRCUITS Figure 18 shows the CS5463 configured to measure power in a single-phase, 2-wire system while operating in a single-supply configuration. In this diagram, a shunt resistor is used to sense the line current and a voltage divider is used to sense the line voltage. In this type of shunt-resistor configuration, the common-mode level of the CS5466 must be referenced to the line side of the power line. This means that the common-mode potential of the CS5463 will track the high-voltage levels, as well as low-voltage levels, with respect to earth ground. Isolation circuitry is required when an earth-ground-referenced communication interface is connected. Figure 19 shows the same single-phase, two-wire system with complete isolation from the power lines. This isolation is achieved using three transformers: a general purpose transformer to supply the on-board DC power; a high-precision, low-impedance voltage transformer, with very little roll-off/phase-delay, to measure voltage; and a current transformer to sense the line current. Figure 20 shows a single-phase, 3-wire system. In many 3-wire residential power systems within the United States, only the two line terminals are available (neutral is not available). Figure 21 shows the CS5463 configured to meter a three-wire system with no neutral available. 5 kΩ N 120 VAC 10 kΩ L 500 Ω 470 nF 500 470 µF 0.1 µF 10 Ω 0.1 µF 14 VA+ 3 VD+ CS5463 9 CVR2 R1 VIN+ CVdiff R VCV+ 10 15 R IR Shunt R I+ C I+ 16 12 IIN+ C IC Idiff VINIIN- 17 PFMON 2 CPUCLK 1 XOUT 24 4.096 MHz Optional Clock Source XIN RESET CS SDI SDO SCLK INT E2 E1 AGND 13 DGND 4 19 ISOLATION 7 23 6 5 20 22 21 Serial Data Interface VREFIN 11 VREFOUT 0.1 µF Note: Indicates common (floating) return. Mech. Counter or Stepper Motor Figure 18. Typical Connection Diagram (Single-phase, 2-wire – Direct Connect to Power Line) DS678F2 41 CS5463 5 kΩ L Voltage Transformer 12 VAC 120 VAC 10 kΩ N 200 Ω 200 Ω 0.1µF 200µF 14 VA+ 10 Ω 0.1 µF 3 VD+ 12 VAC CS5463 M:1 1kΩ R V+ R VC Vdiff 10 9 VIN+ PFMON CPUCLK XOUT 17 2 1 4.096 MHz 24 Optional Clock Source 1kΩ Low Phase-Shift Potential Transformer VIN- XIN N:1 1kΩ RBurden 1kΩ Current Transformer R I15 C Idiff 16 RI+ 12 11 IIN- RESET 19 IIN+ VREFIN VREFOUT AGND 13 7 CS 23 SDI 6 SDO 5 SCLK 20 INT E2 E1 22 21 Serial Data Interface 0.1 µF DGND 4 Mech. Counter or Stepper Motor Figure 19. Typical Connection Diagram (Single-phase, 2-wire – Isolated from Power Line) 240 VAC 120 VAC 120 VAC 5 kΩ L2 500 Ω 500 Ω 470 µF 0.1 µF 10 Ω 0.1 µF 10 kΩ L1 N 470 nF Earth Ground 14 VA+ 3 VD+ CS5463 9 CIdiff VIN+ R3 R2 R1 R4 17 PFMON 2 CPUCLK 1 XOUT 24 4.095 MHz Optional Clock Source 10 1kΩ VIN16 IIN+ XIN R I+ RESET C Idiff 19 RBurden 1kΩ 15 R I- IIN- 12 VREFIN 11 VREFOUT AGND 7 CS 23 SDI 6 SDO 5 SCLK 20 INT E2 E1 22 21 Serial Data Interface 0.1 µF 13 DGND 4 Mech. Counter or Stepper Motor Figure 20. Typical Connection Diagram (Single-phase, 3-wire) 42 DS678F2 CS5463 5 kΩ L2 1 kΩ 500 Ω 470 µF 0.1 µF 10 Ω 0.1 µF 10 kΩ 240 VAC L1 235 nF 14 VA+ 3 VD+ CS5463 9 CV+ VIN+ R1 R2 R V- 17 PFMON 2 CPUCLK 1 XOUT 24 CI+ CVdiff 4.096 MHz Optional Clock Source 10 16 1kΩ VINIIN+ XIN R I+ ISOLATION CIdiff RBurden 1kΩ RESET CS SDI SDO SCLK INT E2 E1 19 7 23 6 5 20 22 21 15 R I- Serial Data Interface IIN- 12 VREFIN 11 VREFOUT AGND 13 0.1 µF DGND 4 Note: Indicates common (floating) return. Mech. Counter or Stepper Motor Figure 21. Typical Connection Diagram (Single-phase, 3-wire – No Neutral Available) DS678F2 43 CS5463 10.PACKAGE DIMENSIONS 24L SSOP PACKAGE DRAWING N D E11 A2 A1 SEATING PLANE E A ∝ L e b2 SIDE VIEW END VIEW 12 3 TOP VIEW DIM A A1 A2 b D E E1 e L ∝ MIN -0.002 0.064 0.009 0.311 0.291 0.197 0.022 0.025 0° INCHES NOM -0.006 0.068 -0.323 0.307 0.209 0.026 0.03 4° MAX 0.084 0.010 0.074 0.015 0.335 0.323 0.220 0.030 0.041 8° MIN -0.05 1.62 0.22 7.90 7.40 5.00 0.55 0.63 0° MILLIMETERS NOM -0.13 1.73 -8.20 7.80 5.30 0.65 0.75 4° NOTE MAX 2.13 0.25 1.88 0.38 8.50 8.20 5.60 0.75 1.03 8° 2,3 1 1 JEDEC #: MO-150 Controlling Dimension is Millimeters. Notes: 3. “D” and “E1” are reference datums and do not included mold flash or protrusions, but do include mold mismatch and are measured at the parting line, mold flash or protrusions shall not exceed 0.20 mm per side. 4. Dimension “b” does not include dambar protrusion/intrusion. Allowable dambar protrusion shall be 0.13 mm total in excess of “b” dimension at maximum material condition. Dambar intrusion shall not reduce dimension “b” by more than 0.07 mm at least material condition. 5. These dimensions apply to the flat section of the lead between 0.10 and 0.25 mm from lead tips. 44 DS678F2 CS5463 11. ORDERING INFORMATION Model Temperature Package CS5463-IS CS5463-ISZ (lead free) -40 to +85 °C 24-pin SSOP 12. ENVIRONMENTAL, MANUFACTURING, & HANDLING INFORMATION Model Number Peak Reflow Temp 240 °C 260 °C MSL Rating* 2 3 Max Floor Life 365 Days 7 Days CS5463-IS CS5463-ISZ (lead free) * MSL (Moisture Sensitivity Level) as specified by IPC/JEDEC J-STD-020. DS678F2 45 CS5463 13. REVISION HISTORY Revision A1 PP1 F1 F2 Date MAR 2005 AUG 2005 NOV 2005 APR 2008 Advance Release First preliminary release. First final release, updated with most-current characterization data. Added PulseWidth & LoadMin Registers. Changes Contacting Cirrus Logic Support For all product questions and inquiries contact a Cirrus Logic Sales Representative. To find the one nearest to you go to www.cirrus.com IMPORTANT NOTICE Cirrus Logic, Inc. and its subsidiaries (“Cirrus”) believe that the information contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided “AS IS” without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights, copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale. CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE IN PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER'S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR PARTICULAR PURPOSE, WITH REGARD TO ANY CIRRUS PRODUCT THAT IS USED IN SUCH A MANNER. IF THE CUSTOMER OR CUSTOMER'S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES, BY SUCH USE, TO FULLY INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER AGENTS FROM ANY AND ALL LIABILITY, INCLUDING ATTORNEYS' FEES AND COSTS, THAT MAY RESULT FROM OR ARISE IN CONNECTION WITH THESE USES. Cirrus Logic, Cirrus, and the Cirrus Logic logo designs are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks or service marks of their respective owners. SPI is a trademark of Motorola, Inc. Microwire is a trademark of National Semiconductor Corporation. 46 DS678F2