X9015US-2.7

X9015 XICOR | Alldatasheet

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Technical content

9900-2009.3 9/20/99 PS Characteristics subject to change without notice Low Noise, Low Power X9015 Digitally-Controlled Potentiometer

FEATURES

• 32 Taps
• Three-wire Up/Down Serial Interface CC = 2.7V & 5V
• Operating I CC = 50µA Max.
• Standby current = 1µA Max. TOTAL = 50K W
• Packages, SOIC-8

DESCRIPTION

The Xicor X9015 is a 32 tap potentiometer that is volatile. The device consists of a string of 31 resistors that can be programmed to connect the R W W wiper output with any of the nodes between the connecting resistors. The connection point of the wiper is determined by information communicated to the device on the 3-wire port. The 3-wire port changes the tap position by a falling edge on the increment pin. Direction the wiper moves is determined by the state of the Up/Down pin. The wiper position at power up is tap #15. The X9015 can be used in a wide variety of applications that require a digitally controlled variable resistor to set analog values. FUNCTIONAL DIAGRAMS 5-BIT UP/DOWN COUNTER CONTR OL CIRCUITRY ONE OF DECODER RESIST OR ARRA Y R H /VHU/D INC CS TRANSFER GATES THIRTY TWO VCC VSS R L/VL R W /VW CONTROL UP/DOWN (U/D) INCREMENT (INC) DEVICE SELECT (CS) VCC (Supply Voltage) VSS (Ground) R H /VH R W /VW R L/VL GENERAL DETAILED

R H H and R L L The high (R H H ) and low (R L L ) terminals of the X9015 are equivalent to the fixed terminals of a mechanical potentiometer. The minimum voltage is V SS and the maximum is V CC . The terminology of R L L and R H H 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. R W W R W w 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 200 W at V CC = 5V. At power up the wiper position is at tap #15 (V L L = tap #0). Up/Down (U/D) The U/D input controls the direction of the wiper movement and whether the tap postion is incremented or decremented. 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. When CS is returned HIGH while the INC input is LOW the X9015 will be placed in the low power standby mode until the device is selected once again. PIN CONFIGURATION PIN NAMES Symbol Description R H H High Terminal R W W Wiper Terminal R L L Low Terminal V SS Ground V CC Supply Voltage U/D Up/Down Control Input INC Increment Control Input CS Chip Select Control Input VCC CS INC U/D R H /VH VSS X9015 SOIC R L/VL R W /VW

There are two sections of the X9015: the input control, counter and decode section; 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 resis- tor array to the wiper output. The resistor array is com- prised of 31 individual resistors connected in series. 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 t IW (INC to V W change). The R TOTAL 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 wiper position is lost. When power is restored, the wiper is set to tap #15. 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 five bit counter. The output of this counter is decoded to select one of thirty two wiper positions along the resistive array. The system may select the X9015, move the wiper and deselect the device. The new wiper position will be maintained until changed by the system or until a power- up/down cycle. 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 SYMBOL TABLE CS INC U/D Mode L H Wiper Up L L Wiper Down H X X Standby Current L X Return to standby WAVEFORM INPUTS OUTPUTS Must be steady Will be steady May change from Lo w to High Will change from Lo w 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

ABSOLUTE MAXIMUM RATINGS* C to +135 C Voltage on CS , INC, U/D, V H , V L and V CC with Respect to V SS D V = |V H L *COMMENT Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and 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 condi- tions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS Temperature Min. Max. Commercial 0°C +70°C Industrial –40°C +85°C Supply Voltage (V CC ) Limits X9015 5V ±10% X9015-2.7 2.7V to 5.5V POTENTIOMETER CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.) Notes: (1) Absolute Linearity is utilized to determine actual wiper voltage versus expected voltage = (V w(n) (actual) – V w(n) (expected)) = ±1 Ml Maximum. (2) Relative Linearity is a measure of the error in step size between taps = V W(n+1) – [V w(n) + Ml] = ±0.2 Ml. (3) 1 Ml = Minimum Increment = R TOT /31. (4) Typical values are for T A = 25°C and nominal supply voltage. (5) This parameter is periodically sampled and not 100% tested. Symbol Parameter Limits Test Conditions/NotesMin. Typ. Max. Units R TOTAL End to End Resistance Variation –20 +20 % V VH V H Terminal Voltage 0 V CC V V VL V L Terminal Voltage 0 V CC V Power Rating 10 mW R TOTAL 50K W R W Wiper Resistance 200 400 W I W = 1mA, V CC = 5V R W Wiper Resistance 400 1000 W I W = 1mA, V CC = 2.7V I W Wiper Current ±1 mA Noise -120 dBV Ref: 1kHz Resolution 3% Absolute Linearity (1) -1 +1 MI(3) Vw(n)(actual) – Vw(n)(expected) Relative Linearity(2) -0.2 +0.2 MI(3) Vw(n+1) – [Vw(n)+MI] R TOTAL Temperature Coefficient ±300 ppm/°C Ratiometric Temperature Coefficient ±20 ppm/°C C H /CL/CW Potentiometer Capacitances 10/10/25 pF See circuit #3

D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified.) Symbol Parameter Limits Units Test ConditionsMin. Typ. (4) Max. ICC1 VCC Active Current (Increment) 50 µA CS = VIL, U/D = VIL or VIH and INC = 0.4V @ max. tCYC ISB Standby Supply Current 1 µA CS = VCC – 0.3V, U/D and INC = VSS or VCC – 0.3V ILI CS , INC, U/D Input ±10 µA VIN = VSS to VCC Leakage Current VIH CS , INC, U/D Input VCC x 0.7 V CC + 0.5 V HIGH Voltage VIL CS , INC, U/D Input –0.5 VCC x 0.1 V LOW Voltage C IN(5) CS , INC, U/D Input 10 pF VCC = 5V, VIN = VSS , Capacitance TA = 25°C, f = 1MHz Test Circuit #2 FORCE CURRENTVL VW VH TEST POINT Test Circuit #1 TEST POINT VW /RW VH /RH VL/RL VS Test Circuit #2 FORCE CURRENT VL VW VH TEST POINT Test Circuit #2 FORCE CURRENT VL VW POINT VH /RH VW /RW VL/RL Circuit #3 SPICE Macromodel C H C L R W 10pF 10pF R H R L R TOTAL C W 25pF

A.C. CONDITIONS OF TEST Input Pulse Levels 0V to 3V Input Rise and Fall Times 10ns Input Reference Levels 1.5V A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified) A.C. TIMING 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 V W output due to a change in the wiper position. Symbol Parameter Limits UnitsMin. Typ. (6) Max. 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 100 ns tIW INC to Vw Change 1 5 µs tCYC INC Cycle Time 4 µs tR , tF(7) INC Input Rise and Fall Time 500 µs tPU (7) Power up to Wiper Stable 5 µs tR VCC (7) VCC Power-up Rate 0.2 50 V/ms CS INC U/D VW tCI tIL tIH tCYC tID tDI tIW MI (8) tCPH tF tR 10% 90% 90% (Stand by) tIC

PERFORMANCE CHARACTERISTICS (TYPICAL) TYPICAL NOISE TYPICAL RTOTAL vs. TEMPERATURE TYPICAL TOTAL RESISTANCE TEMPERATURE COEFFICIENT -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 -150 0 1 02 03 04 05 06 07 08 09 0 1 0 0 Frequency (KHz) Noise (dB) 110 120 130 140 150 160 170 180 190 200 10000 9800 9600 9400 9200 9000 8800 8600 8400 8200 8000 Rtotal -55 -45 -35 -25 -15 -5 5 15 25 35 45 55 65 75 Temperature 85 95 105 115 125 C° -55 -350 -300 -250 -200 -150 -100 -50 -45 -35 -25 -15 -5 5 15 25 35 Temperature PPM 45 55 65 75 85 95 105 115 125 °C

TYPICAL ABSOLUTE % ERROR PER TAP POSITION TYPICAL RELATIVE % ERROR PER TAP POSITION 100 200 300 400 Rw (Ohms) 500 600 700 800 2468 1 0 1 2 1 4 1 6 Tap 18 20 22 24 26 28 30 32 VCC = 2.7V 40.0% 30.0% 20.0% 10.0% 0.0% -10.0% -20.0% -30.0% -40.0% 0369 1 2 1 5 Tap Absolute % Error 18 21 24 27 30 20.0% 15.0% 10.0% 5.0% 0.0% -5.0% -10.0% -15.0% -20.0% 0369 1 2 1 5 Ta p Relative % Error 18 21 24 27 30

Electronic digitally-controlled (XDCP) potentiometers provide two powerful application advantages; (1) the variability and reliability of a solid-state potentiometer, and (2) the flexibility of computer-based digital controls. Basic Configurations of Electronic Potentiometers Basic Circuits VR VW VR I Three terminal potentiometer; variable voltage divider Two terminal variable resistor; variable current VH VL Cascading TechniquesBuffered Reference Voltage +5V R 1 –5V VW VREF VOUT OP-07 VW VW +V +V X (a) (b) VOUT = VW Noninverting Amplifier VS VO R 2 R 1 VO = (1+R2/R1)VS LM308A Voltage Regulator R 1 R 2 Iadj VO (REG) = 1.25V (1+R2/R1)+Iadj R2 VO (REG)VIN 317 Offset Voltage Adjustment VS VO R 2R 1 100KW 10KW10KW 10KW -12V+12V TL072 Comparator with Hysterisis VUL = {R1/(R1+R 2)} VO (max) VLL = {R1/(R1+R 2)} VO (min) –VS VO R 2R 1 LT311A +5V –5V (for additional circuits see AN115)

SOIC PACKAGING INFORMATION 0.150 (3.80) 0.158 (4.00) 0.228 (5.80) 0.244 (6.20) 0.014 (0.35) 0.019 (0.49) PIN 1 PIN 1 INDEX 0.010 (0.25) 0.020 (0.50) 0.050 (1.27) 0.188 (4.78) 0.197 (5.00) 0.004 (0.19) 0.010 (0.25) 0.053 (1.35) 0.069 (1.75) (4X) 7° 0.016 (0.410) 0.037 (0.937) 0.0075 (0.19) 0.010 (0.25) 0° – 8° X 45° 8-LEAD PLASTIC SMALL OUTLINE GULL WING P ACKAGE TYPE S NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) 0.250" 0.050" TYPICAL 0.050" TYPICAL 0.030" TYPICAL

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ORDERING INFORMATION

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, licenses are implied. U.S. PATENTS Xicor products are covered by one or more of the following U.S. Patents: 4,263,664; 4,274,012; 4,300,212; 4,314,265; 4,326,134; 4,393,481; 4,883, 976. 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. VCC Limits Blank = 5V –10% Temperature Range Blank = Commercial = 0°C to +70°C I = Industrial = –40°C to +85°C Package S = 8-Lead SOIC End to End Resistance U = 50KW X9015 XX Physical Characteristics Marking Includes Manufacturer’s Trademark Resistance Value or Code Date Code X