X9116

APPLICATION NOTE AVAILABLE AN99 • AN115 • AN120 • AN124 • AN133 • AN134 Low Noise, Low Power, Low Cost X9116 Digitally Controlled Potentiometer (XDCP™) FEATURES • • • • • • • • Solid-state nonvolatile 16 wiper taps 3-wire up/down serial interface VCC = 2.7V and 5V Active current < 50µA max. Standby current < 1µA max. RTOTAL = 10KΩ Packages: MSOP-8, SOIC DESCRIPTION The Xicor X9116 is a digitally controlled nonvolatile potentiometer designed to be used in trimmer applications. The pot consists of 15 equal resistor segments that connect to the wiper pin through programmable CMOS switches. The tap position is programmed through a 3-wire up/down serial port. The last position of the wiper is stored in a nonvolatile memory location which is recalled at the time of power up of the device. The wiper moves through sequential tap positions with inputs on the serial port. A falling edge on INC (bar) causes the tap position to increment one position up or down based on whether the U/D (bar) pin is held high or low. The X9116 can be used in many applications requiring a variable resistance. In many cases it can replace a mechanical trimmer and offers many advantages such as temperature and time stability as well as the reliability of a solid state solution. BLOCK DIAGRAM VCC (Supply Voltage) Up/Down (U/D) Increment (INC) Device Select (CS) Control and Memory RH/VH RW/VW RL/VL VSS (Ground) General RH 13 * 3 2 1 RL 0 RW-RL Resistance 15 14 10kΩ 9.34kΩ 8.68kΩ * kΩ 2.08kΩ 1.42kΩ 760Ω 100Ω REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 1 of 11 X9116 PIN DESCRIPTIONS VH /RH and VL /RL The high (VH/RH) and low (VL/RL) terminals of the X9116 are equivalent to the fixed terminals of a mechanical potentiometer. The minimum voltage is VSS and the maximum is VCC. VW/RW Rw/Rw is the wiper terminal and is 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 200Ω to 400Ω depending upon VCC. Up/Down (U/D) The U/D input controls the direction of the wiper movement and whether the counter is incremented (up) or decremented (down). 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 HIGH. After the store operation is complete the X9116 will be placed in the low power standby mode until the device is selected once again. PIN CONFIGURATION SOIC/MSOP INC U/D VH/RH VSS 1 2 3 4 X9116 8 7 6 5 VCC CS VL/RL VW/RW PIN NAMES Symbol VH/RH VW/RW VL/RL VSS VCC U/D INC CS Description High Terminal Wiper Terminal Low Terminal Ground Supply Voltage Up/Down Control Input Increment Control Input Chip Select Input PRINCIPLES OF OPERATION There are three sections of the X9116: 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 15 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 pin. 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. The electronic switches on the device 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. When the device is powered-down, the last wiper position stored will be maintained in the nonvolatile memory. When power is restored, the contents of the memory are recalled and the wiper is set to the value last stored. REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 2 of 11 X9116 INSTRUCTIONS AND PROGRAMMING The INC, U/D and CS inputs control the movement of the wiper along the resistor array. With CS set LOW, the device 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 four bit counter. The output of this counter is decoded to select one of 16 wiper positions along the resistive array. The value of the counter is stored in nonvolatile memory whenever CS transitions HIGH while the INC input is also HIGH. The system may select the X9116, move the wiper, and deselect the device without having to store the latest wiper position in nonvolatile memory. After the wiper movement is performed as described above and once the new position is reached, the system must keep INC LOW while taking CS HIGH. The new wiper position will be maintained until changed by the system or until a power-up/down cycle recalls the previously stored data. This procedure allows 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 device and then move the wiper up and down until the proper trim is attained. MODE SELECTION CS L L H H X L INC U/D H L X X X Wiper Up Mode Wiper Down Store Wiper Position Standby Current No Store, Return to Standby SYMBOL TABLE WAVEFORM INPUTS Must be steady May change from Low to High May change from High to Low Don’t Care: Changes Allowed N/A OUTPUTS Will be steady Will change from Low to High Will change from High to Low Changing: State Not Known Center Line is High Impedance REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 3 of 11 X9116 ABSOLUTE MAXIMUM RATINGS Temperature under bias ....................–65°C to +135°C Storage temperature .........................–65°C to +150°C Voltage on CS, INC, U/D, VH/RH, VL/RL and VCC with respect to VSS ................... –1V to +7V ∆V = |VH/RH–VL/RL| ............................................ 5.5V Lead temperature (soldering 10 seconds)..........300°C IW (10 seconds) ............................................ ±10.0mA COMMENT Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only; the 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 Commercial Industrial Min. 0°C –40°C Max. +70°C +85°C Supply Voltage (VCC) X9116 X9116-2.7 Limits 5V ±10% 2.7V to 5.5V POTENTIOMETER CHARACTERISTICS (Over recommended operating conditions unless otherwise stated) Limits Symbol RTOTAL VVH VVL RW RW IW Parameter End to end resistance variation VH/RH terminal voltage VL/RL terminal voltage Power rating Wiper resistance Wiper resistance Wiper current Noise Resolution Absolute linearity (1) Min. –20 VSS VSS Typ. Max. +20 VCC VCC 10 Unit % V V mW Ω Ω mA Test Conditions/Notes VSS = 0V VSS = 0V RTOTAL = 10 KΩ IW = 1mA, VCC = 5V IW = 1mA, VCC = 2.7V 200 400 -5.0 -120 6 -1 -0.2 ±300 400 1000 +5.0 dBV√Hz Ref: 1kHz % +1 +0.2 ±20 MI(3) MI(3) ppm/°C ppm/°C pF See Circuit #3 Vw(n)(actual)–Vw(n)(expected) Vw(n+1)–[Vw(n)+MI] Relative linearity(2) RTOTAL temperature coefficient Ratiometric temperature coefficient CH/CL/CW Potentiometer capacitances 10/10/25 Notes: (1) Absolute linearity is utilized to determine actual wiper voltage versus expected voltage = (Vw(n)(actual)–Vw(n)(expected)) = ±1 Ml Maximum. (2) Relative linearity is a measure of the error in step size between taps = VW(n+1)–[Vw(n) + Ml] = ±0.2 Ml. (3) 1 Ml = Minimum Increment = RTOT/15. REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 4 of 11 X9116 D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified) Limits Symbol ICC1 ICC2 ISB ILI VIH VIL CIN(5) Parameter VCC active current (Increment) VCC active current (Store) (EEPROM Store) Standby supply current CS, INC, U/D input leakage current CS, INC, U/D input HIGH voltage CS, INC, U/D input LOW voltage CS, INC, U/D input capacitance Min. Typ.(4) Max. 150 400 1 ±10 Unit µA µA µA µA V V pF Test Conditions CS = VIL, U/D = VIL or VIH and INC = 0.4V/2.4V @ max. tCYC CS = VIH, U/D = VIL or VIH and INC = VIH @ max. tWR CS = VCC–0.3V, U/D and INC = VSS or VCC–0.3V VIN = VSS to VCC 2V –0.5 VCC + 0.5 0.8 10 VCC = 5V, VIN = VSS, TA = 25°C, f = 1MHz Notes: (4) Typical values are for TA = 25°C and nominal supply voltage. (5) This parameter is periodically sampled and not 100% tested. ENDURANCE AND DATA RETENTION Parameter Minimum endurance Data retention Min. 100,000 100 Unit Data changes per bit Years Test Circuit #1 VH/RH Test Circuit #2 VH/RH Circuit #3 SPICE Macro Model RTOTAL RH Test Point CH 10pF RW CW 25pF CL 10pF RL VS Test Point VW/RW VL/RL VW/RW VW VL /RL L Force Current A.C. CONDITIONS OF TEST Input pulse levels Input rise and fall times Input reference levels 0V to 3V 10ns 1.5V REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 5 of 11 X9116 A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified) Limits Symbol tCl tlD tDI tlL tlH tlC tCPH tIW tCYC tR, tF(7) tPU(7) tR VCC(7) tWR Parameter CS to INC setup INC HIGH to U/D change U/D to INC setup INC LOW period INC HIGH period INC inactive to CS inactive CS deselect time (STORE) INC to Vw change INC cycle time INC input rise and fall time Power up to wiper stable VCC Power-up rate Store cycle Min. 100 100 2.9 1 1 1 10 Typ.(6) Max. Unit ns ns µs µs µs µs ms 1 4 5 500 5 µs µs µs µs mV/µs ms 15 5 50 10 POWER UP AND DOWN REQUIREMENTS There are no restrictions on the power-up or power-down conditions of VCC and the voltages applied to the potentiometer pins provided that VCC is always more positive than or equal to VH, VL, and VW, i.e., VCC ≥ VH, VL, VW. The VCC ramp rate spec is always in effect. A.C. TIMING CS tCYC tCI INC tID tDI tF tIL tIH tIC (store) tCPH 90% 90% 10% tR U/D tIW VW MI (8) Notes: (6) Typical values are for TA = 25°C and nominal supply voltage. (7) This parameter is 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 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 6 of 11 X9116 Basic Configurations of Electronic Potentiometers VR VH VW/RW VL I Three terminal potentiometer; variable voltage divider Two terminal variable resistor; variable current VR Basic Circuits Buffered Reference Voltage R1 +V +5V VREF VW + – –5V VOUT = VW/RW (a) (b) OP-07 VOUT +V R1 VW VO = (1+R2/R1)VS VW/RW X Cascading Techniques +V +V VS + – –5V R2 Noninverting Amplifier +5V LM308A VO Voltage Regulator Comparator with Hysteresis VIN 317 R1 VO (REG) VS LT311A – + VO Iadj R2 VO (REG) = 1.25V (1+R2/R1)+Iadj R2 VUL = {R1/(R1+R2)} VO(max) VLL = {R1/(R1+R2)} VO(min) (for additional circuits see AN115) } R1 } R2 7 of 11 REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. X9116 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) 7° Typ. 0.040 ± 0.002 (1.02 ± 0.05) 0.008 (0.20) 0.004 (0.10) 0.0256" Typical 0.007 (0.18) 0.005 (0.13) 0.150 (3.81) Ref. 0.193 (4.90) Ref. 0.025" Typical 0.220" FOOTPRINT 0.020" Typical 8 Places NOTE: 1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS) REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 8 of 11 X9116 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) 7° Typ. 0.040 ± 0.002 (1.02 ± 0.05) 0.008 (0.20) 0.004 (0.10) 0.0256" Typical 0.007 (0.18) 0.005 (0.13) 0.150 (3.81) Ref. 0.193 (4.90) Ref. 0.025" Typical 0.220" FOOTPRINT 0.020" Typical 8 Places NOTE: 1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS) REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 9 of 11 X9116 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° - 8° 0.0075 (0.19) 0.010 (0.25) 0.016 (0.410) 0.037 (0.937) 0.250" 0.050" Typical FOOTPRINT 0.030" Typical 8 Places NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) REV 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 10 of 11 X9116 Ordering Information X9116X X X X VCC Limits Blank = 5V ±10% –2.7 = 2.7V to 5.5V Temperature Range Blank = Commercial = 0°C to +70°C I = Industrial = –40°C to +85°C Package M8 = 8-Lead MSOP S8 = 8-Lead SOIC End to End Resistance W= 10KΩ 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 occurrence. 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 1.2 2/5/03 www.xicor.com Characteristics subject to change without notice. 11 of 11