X9314WSI

APPLICATION NOTE A V A I L A B L E AN42 • AN44–50 • AN52 • AN53 • AN71 • AN73 • AN99 • AN115 • AN120 • AN124 • AN134 Terminal Voltages ±5V, 32 Taps, Log Taper X9314 Single Digitally Controlled Potentiometer (XDCP™) FEATURES DESCRIPTION • • • • • • The Xicor X9314 is a solid state nonvolatile potentiometer and is ideal for digitally controlled resistance trimming. Solid State Potentiometer 32 Taps 10KΩ End to End Resistance Three-Wire Up/Down Serial Interface Wiper Resistance, 40Ω Typical Nonvolatile Storage and Recall on Power Up of Wiper Position Standby Current < 500µA Max (Total Package) • VCC = 3V to 5.5V Operation • 100 Year Data Retention • Offered in MSOP, SOIC Packages The X9314 is a resistor array composed of 31 resistive elements. Between each element and at either end are tap points accessible to the wiper element. The position of the wiper element is controlled by the CS, U/D, and INC inputs. The position of the wiper can be stored in nonvolatile memory and then be recalled upon a subsequent power-up operation. The XDCP can be used as a three-terminal potentiometer or as a two-terminal variable resistor in a wide variety of applications including control, parameter adjustments, and signal processing. BLOCK DIAGRAM U/D INC CS 31 5-Bit Up/Down Counter VH/RH 30 29 5-Bit Nonvolatile Memory 28 One of Thirty-Two Decoder Transfer Gates Resistor Array 2 Store and Recall Control Circuitry 1 0 VCC VSS VL/RL VW/RW XDCP is a trademark of Xicor, Inc. REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 1 of 9 X9314 PIN DESCRIPTIONS VH/RH and VL/RL The high (VH/RH) and low (VL/RL) terminals of the X9314 are equivalent to the fixed terminals of a mechanical potentiometer. The minimum voltage is – 5V and the maximum is +5V. It should be noted that the terminology of VL/RL and VH/RH references the relative position of the terminal in relation to wiper movement direction selected by the U/D input and not the voltage potential on the terminal. HIGH. After the store operation is complete the X9314 will be placed in the low power standby mode until the device is selected once again. PIN CONFIGURATION 8-Lead DIP/SOIC VW/RW VW/RW is the wiper terminal, equivalent to the movable terminal of a mechanical potentiometer. The position of the wiper within the array is determined by the control inputs. The wiper terminal series resistance is typically 40Ω. Up/Down (U/D) The U/D input controls the direction of the wiper movement and whether the counter is incremented or decremented. INC 1 8 VCC U/D 2 7 CS 6 VL/RL 5 VW/RW VH/RH 3 VSS 4 X9314 8-Lead MSOP VH/RH 1 VSS 2 VW/RW 3 VL/RL 4 X9314 8 U/D 7 6 INC VCC 5 CS PIN NAMES Increment (INC) The INC input is negative-edge triggered. Toggling INC will move the wiper and either increment or decrement the counter in the direction indicated by the logic level on the U/D input. Chip Select (CS) The device is selected when the CS input is LOW. The current counter value is stored in nonvolatile memory when CS is returned HIGH while the INC input is also Symbol Description VH/RH High Terminal VW/RW Wiper Terminal VL/RL Low Terminal VSS Ground VCC Supply Voltage U/D Up/Down Input INC Increment Input CS Chip Select Input Typical Attenuation Characteristics (dB) Attenuation (dB) 0 -20 -40 -43.5 -60 31 REV 1.1 11/10/00 28 24 20 16 Tap Position www.xicor.com 12 8 4 Characteristics subject to change without notice. 0 2 of 9 X9314 PRINCIPLES OF OPERATION There are three sections of the X9314: the input control, counter and decode section; the nonvolatile memory; and the resistor array. The input control section operates just like an up/down counter. The output of this counter is decoded to turn on a single electronic switch connecting a point on the resistor array to the wiper output. Under the proper conditions the contents of the counter can be stored in nonvolatile memory and retained for future use. The resistor array is comprised of 31 individual resistors connected in series. At either end of the array and between each resistor is an electronic switch that transfers the potential at that point to the wiper. The INC, U/D and CS inputs control the movement of the wiper along the resistor array. With CS set LOW the X9314 is selected and enabled to respond to the U/D and INC inputs. HIGH to LOW transitions on INC will increment or decrement (depending on the state of the U/D input) a five bit counter. The output of this counter is decoded to select one of thirty-two wiper positions along the resistive array. The wiper, when at either fixed terminal, acts like its mechanical equivalent and does not move beyond the last position. That is, the counter does not wrap around when clocked to either extreme. movement is performed as described above; once the new position is reached, the system would keep the INC LOW while taking CS HIGH. The new wiper position would be maintained until changed by the system or until a power-up/down cycle recalled the previously stored data. This would allow the system to always power-up to a preset value stored in nonvolatile memory; then during system operation minor adjustments could be made. The adjustments might be based on user preference, system parameter changes due to temperature drift, etc... The state of U/D may be changed while CS remains LOW. This allows the host system to enable the X9314 and then move the wiper up and down until the proper trim is attained. tIW/RTOTAL The electronic switches on the X9314 operate in a “make before break” mode when the wiper changes tap positions. If the wiper is moved several positions multiple taps are connected to the wiper for tIW (INC to VW change). The RTOTAL value for the device can temporarily be reduced by a significant amount if the wiper is moved several positions. SYMBOL TABLE The value of the counter is stored in nonvolatile memory whenever CS transistions HIGH while the INC input is also HIGH. When the X9314 is powered-down, the last counter position stored will be maintained in the nonvolatile memory. When power is restored, the contents of the memory are recalled and the counter is reset to the value last stored. Operation Notes The system may select the X9314, move the wiper and deselect the device without having to store the latest wiper position in nonvolatile memory. The wiper REV 1.1 11/10/00 www.xicor.com WAVEFORM INPUTS OUTPUTS Must be steady Will be steady May change from Low to High Will change from Low to High May change from High to Low Will change from High to Low Don’t Care: Changes Allowed Changing: State Not Known N/A Center Line is High Impedance Characteristics subject to change without notice. 3 of 9 X9314 ABSOLUTE MAXIMUM RATINGS COMMENT Temperature under bias ....................–65°C to +135°C Storage temperature .........................–65°C to +150°C Voltage on CS, INC, U/D, and VCC with respect to VSS ......................... –1V to +7V Voltage on VH/RH and VL/RL referenced to VSS.......................................................-8V to +8V ∆V = |VH/RH–VL/RL|.............................................. 10V Lead temperature (soldering 10 seconds)..........300°C Wiper current ..................................................... ±1mA IW (10 seconds) .............................................. ±8.8mA Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only; functional operation of the device (at these or any other conditions above those listed in the operational sections of this specification) is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS Temperature Min. Max. Supply Voltage (VCC) Limits Commercial 0°C +70°C X9314 5V ±10% Industrial –40°C +85°C X9314-3 3V to 5.5V POTENTIOMETER CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.) Limits Symbol Parameter RTOTAL End to End Resistance Tolerance VVL/RL Min. Typ. Max. Units ±20 % VH/RH Terminal Voltage -5 +5 V VL/RL Terminal Voltage -5 +5 V Power Rating RW Wiper Resistance IW Wiper Current 40 Noise Relative variation. Error in step size between taps. mW Ω ±4.4 mA -120 0.070.003 dBV ±600 Ratiometric Temperature Coefficient ppm/°C ±20 10/10/25 pF at 25°C IW = ±1mA, VCC = 5V Ref: 1kHz log (Rw(n))–log Rw(n-1)) 0.07 + 0.003 RTOTAL Temperature Coefficient CH/CL/CW Potentiometer Capacitance 10 100 Test Conditions/ Notes for -40°C to +85°C ppm/°C See Circuit #3 Notes: (1) This parameter is periodically sampled and not 100% tested. POWER UP AND DOWN REQUIREMENT The are no restrictions on the sequencing of VCC and the voltages applied to the potentiometer pins during powerup or power-down conditions. During power-up, the data sheet parameters for the DCP do not fully apply until 1 millisecond after VCC reaches its final value. The VCC ramp rate spec is always in effect. REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 4 of 9 X9314 D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified.) Limits Symbol Parameter Min. Typ.(4) Max. Units 1 3 mA CS = VIL, U/D = VIL or VIH and INC = 0.4V/2.4V @ max. tCYC Test Conditions ICC VCC Active Current ISB Standby Supply Current 500 µA CS = VCC – 0.3V, U/D and INC = VSS or VCC – 0.3V ILI CS, INC, U/D Input Leakage Current ±10 µA VIN = VSS to VCC VIH CS, INC, U/D Input HIGH Voltage 2 VCC + 1 V VIL CS, INC, U/D Input LOW Voltage –1 0.8 V CIN(5) CS, INC, U/D Input Capacitance 10 pF VCC = 5V, VIN = VSS, TA = 25°C, f = 1MHz STANDARD PARTS Part Number Maximum Resistance Wiper Increments Minimum Resistance X9314W 10KΩ Log Taper 40Ω Notes: (4) Typical values are for TA = 25°C and nominal supply voltage. (5) This parameter is periodically sampled and not 100% tested. Test Circuit #1 Test Circuit #2 Circuit #3 SPICE Macromodel Macro Model VH/RH VH/RH RTOTAL Test Point Test Point VW/RW RH CH VW/RW Force Current CW 10pF VL/RL VL/RL RL CL 10pF 25pF RW A.C. CONDITIONS OF TEST MODE SELECTION Input Pulse Levels 0V to 3V CS Input rise and fall times 10ns L H Wiper up Input reference levels 1.5V L L Wiper down H X Store wiper position X X Standby L X No store, return to standby H REV 1.1 11/10/00 www.xicor.com INC U/D Mode Characteristics subject to change without notice. 5 of 9 X9314 A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified) Limits Symbol Parameter Min. Typ.(6) Max. Units tCl CS to INC Setup 100 ns tlD INC HIGH to U/D Change 100 ns tDI U/D to INC Setup 2.9 µs tlL INC LOW Period 1 µs tlH INC HIGH Period 1 µs tlC INC Inactive to CS Inactive 1 µs tCPH CS Deselect Time 20 ms tIW INC to VW Change 100 INC Cycle Time tCYC tR, tF(7) (7) tPU tR VCC 500 4 µs µs INC Input Rise and Fall Time 500 µs Power up to Wiper Stable 500 µs 50 mV/µs VCC Power-up Rate 0.2 A.C. Timing CS tCYC tIL tCI tIC tIH tCPH 90% 90% 10% INC tID tDI tF tR U/D tIW VW MI (8) Notes: (6) Typical values are for TA = 25°C and nominal supply voltage. (7) This parameter is periodically sampled and not 100% tested. (8) MI in the A.C. timing diagram refers to the minimum incremental change in the VW output due to a change in the wiper position. REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 6 of 9 X9314 PACKAGING INFORMATION 8-Lead Miniature Small Outline Gull Wing Package Type M 0.118 ± 0.002 (3.00 ± 0.05) 0.012 + 0.006 / -0.002 (0.30 + 0.15 / -0.05) 0.0256 (0.65) Typ. R 0.014 (0.36) 0.118 ± 0.002 (3.00 ± 0.05) 0.030 (0.76) 0.0216 (0.55) 0.036 (0.91) 0.032 (0.81) 0.040 ± 0.002 (1.02 ± 0.05) 7° Typ. 0.008 (0.20) 0.004 (0.10) 0.0256" Typical 0.007 (0.18) 0.005 (0.13) 0.025" Typical 0.150 (3.81) Ref. 0.193 (4.90) Ref. 0.220" 0.020" Typical 8 Places FOOTPRINT NOTE: 1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS) REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 7 of 9 X9314 PACKAGING INFORMATION 8-Lead Plastic Small Outline Gull Wing Package Type S 0.150 (3.80) 0.228 (5.80) 0.158 (4.00) 0.244 (6.20) Pin 1 Index Pin 1 0.014 (0.35) 0.019 (0.49) 0.188 (4.78) 0.197 (5.00) (4X) 7° 0.053 (1.35) 0.069 (1.75) 0.004 (0.19) 0.010 (0.25) 0.050 (1.27) 0.010 (0.25) X 45° 0.020 (0.50) 0.050"Typical 0.050" Typical 0° - 8° 0.0075 (0.19) 0.010 (0.25) 0.250" 0.016 (0.410) 0.037 (0.937) 0.030" Typical 8 Places FOOTPRINT NOTE: ALL DIMENSIONS IN INCHES (IN P ARENTHESES IN MILLIMETERS) REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 8 of 9 X9314 Ordering Information X9314 XDCP 10KΩ, Log Taper X9314W X X X VCC Range Blank = VCC = 5V ±10% 3 = VCC = 3V to 5.5V (Not available in Industrial Temperature) Temperature Range Blank = 0°C to +70°C I = –40°C to +85°C Package M = 8-Lead MSOP S = 8-Lead SOIC End to End Resistance W = 10KΩ Part Mark Convention X9314W X Blank = 8-Lead SOIC (Date Code) X Blank = 5V ±10%, 0°C to 70°C I = 5V ±10%, -40°C to +85°C D = 3V to 5.5V, 0°C to 70°C E = 3V to 5.5V, -40°C to +85°C LIMITED WARRANTY ©Xicor, Inc. 2000 Patents Pending Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc. makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. Xicor, Inc. makes no warranty of merchantability or fitness for any purpose. Xicor, Inc. reserves the right to discontinue production and change specifications and prices at any time and without notice. Xicor, Inc. assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xicor, Inc. product. No other circuits, patents, or licenses are implied. TRADEMARK DISCLAIMER: Xicor and the Xicor logo are registered trademarks of Xicor, Inc. AutoStore, Direct Write, Block Lock, SerialFlash, MPS, and XDCP are also trademarks of Xicor, Inc. All others belong to their respective owners. U.S. PATENTS Xicor products are covered by one or more of the following U.S. Patents: 4,326,134; 4,393,481; 4,404,475; 4,450,402; 4,486,769; 4,488,060; 4,520,461; 4,533,846; 4,599,706; 4,617,652; 4,668,932; 4,752,912; 4,829,482; 4,874,967; 4,883,976; 4,980,859; 5,012,132; 5,003,197; 5,023,694; 5,084,667; 5,153,880; 5,153,691; 5,161,137; 5,219,774; 5,270,927; 5,324,676; 5,434,396; 5,544,103; 5,587,573; 5,835,409; 5,977,585. Foreign patents and additional patents pending. LIFE RELATED POLICY In situations where semiconductor component failure may endanger life, system designers using this product should design the system with appropriate error detection and correction, redundancy and back-up features to prevent such an occurence. Xicor’s products are not authorized for use in critical components in life support devices or systems. 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. REV 1.1 11/10/00 www.xicor.com Characteristics subject to change without notice. 9 of 9