19-4599; Rev 2; 1/10 TION KIT EVALUA BLE IL AVA A Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers The MAX5386/MAX5388 dual, 256-tap, volatile, low-voltage linear taper digital potentiometers offer three end-to-end resistance values of 10kI, 50kI, and 100kI. Operating from a single +2.6V to +5.5V power supply these devices provide a low 35ppm/NC end-to-end temperature coefficient. The devices feature an SPIK interface. The small package size, low supply voltage, low supply current, and automotive temperature range of the MAX5386/MAX5388 make the devices uniquely suitable for the portable consumer market, battery backup industrial applications, and the automotive market. The MAX5386 includes two digital potentiometers in a voltage-divider configuration. The MAX5388 includes one digital potentiometer in a voltage-divider configuration and one digital potentiometer in a variable-resistor configuration. The MAX5386/MAX5388 are specified over an extended -40NC to +125NC temperature range and are available in 16-pin, 3mm x 3mm TQFN or 10-pin, 3mm x 5mm FMAXM packages, respectively. Applications Low-Voltage Battery Applications Portable Electronics Features S Dual, 256-Tap, Linear Taper Positions S Single +2.6V to +5.5V Supply Operation S Low (< 1µA) Quiescent Supply Current S 10kI, 50kI, 100kI End-to-End Resistance Values S SPI-Compatible Interface S Power-On Sets Wiper to Midscale S -40NC to +125NC Operating Temperature Range Ordering Information PINPACKAGE PART END-TO-END RESISTANCE (kI) MAX5386LATE+ 16 TQFN-EP* MAX5386MATE+ 16 TQFN-EP* 10 50 MAX5386NATE+ 16 TQFN-EP* 100 MAX5388LAUB+ 10 FMAX 10 MAX5388MAUB+ 10 FMAX 50 MAX5388NAUB+ 10 FMAX 100 Mechanical Potentiometer Replacement Note: All devices are specified over the -40°C to +125°C operating temperature range. Offset and Gain Control +Denotes a lead(Pb)-free/RoHS-compliant package. Adjustable Voltage References/Linear Regulators *EP = Exposed pad. Automotive Electronics Functional Diagrams appear at end of data sheet. SPI is a trademark of Motorola, Inc. µMAX is a registered trademark of Maxim Integrated Products, Inc. N.C. SCLK DIN TOP VIEW VDD Pin Configurations 12 11 10 9 N.C. 13 8 HA 14 MAX5386 WA 15 *EP 1 2 3 4 WB LB I.C. + HB LA 16 TOP VIEW CS 7 N.C. 6 N.C. 5 GND GND 1 LB 2 + 10 LA 9 WA HB 3 8 VDD WB 4 7 SCLK CS 5 6 DIN MAX5388 µMAX TQFN *EP = EXPOSED PAD. ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX5386/MAX5388 General Description MAX5386/MAX5388 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers ABSOLUTE MAXIMUM RATINGS VDD to GND..............................................................-0.3V to +6V H_, W_, L_ to GND.....-0.3V to the lower of (VDD + 0.3V) and +6V All Other Pins to GND..............................................-0.3V to +6V Continuous Current in to H_, W_, and L_ MAX5386L/MAX5388L.................................................... ±5mA MAX5386M/MAX5388M.................................................. Q2mA MAX5386N/MAX5388N.................................................. Q1mA Continuous Power Dissipation (TA = +70NC) 16 TQFN (derate 14.7mW/NC above +70NC)..........1176.5mW 10 FMAX (derate 8.8mW/NC above +70NC)..............707.3mW Operating Temperature Range......................... -40NC to +125NC Junction Temperature......................................................+150NC Storage Temperature Range............................. -65NC to +150NC Lead Temperature (soldering, 10s).................................+300NC Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = +2.6V to +5.5V, VH_ = VDD, VL_ = GND, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VDD = +5V, TA = +25˚C. ) (Note 1) PARAMETER Resolution SYMBOL CONDITIONS N MIN TYP MAX 256 UNITS Tap DC PERFORMANCE (VOLTAGE-DIVIDER MODE) Integral Nonlinearity INL (Note 2) -0.5 +0.5 LSB Differential Nonlinearity DNL (Note 2) -0.5 +0.5 LSB Dual Code Matching Register A = register B -0.5 +0.5 Ratiometric Resistor Tempco (DVW/VW)/DT no load Full-Scale Error Code = FFH MAX5386L/MAX5388L -3.0 MAX5386M/MAX5388M -1.0 -0.5 MAX5386N/MAX5388N -0.5 -0.25 MAX5386L/MAX5388L Zero-Scale Error Code = 00H LSB ppm/NC Q5 -2.5 LSB 2.5 3.0 MAX5386M/MAX5388M +0.5 +1.0 MAX5386N/MAX5388N +0.25 +0.5 MAX5386L/MAX5388L Q1.0 Q2.5 MAX5386M/MAX5388M Q0.5 Q1.0 MAX5386N/MAX5388N Q0.25 Q0.8 MAX5386L/MAX5388L Q0.4 Q1.5 MAX5386M/MAX5388M Q0.3 Q0.75 MAX5386N/MAX5388N Q0.25 Q0.5 LSB DC PERFORMANCE (VARIABLE-RESISTOR MODE) (Note 3) VDD > +2.6V Integral Nonlinearity R-INL VDD > +4.75V Differential Nonlinearity R-DNL -0.5 VDD R 2.6V +0.5 LSB LSB DC PERFORMANCE (RESISTOR CHARACTERISTICS) Wiper Resistance (Note 4) Terminal Capacitance RW VDD R 2.6V 250 600 VDD > 4.75V 150 200 I CH_, CL_ Measured to GND 10 Wiper Capacitance CW_ Measured to GND 50 pF End-to-End Resistor Tempco TCR No load 35 ppm/NC End-to-End Resistor Tolerance DRHL Wiper not connected -25 pF +25 % AC PERFORMANCE Crosstalk -3dB Bandwidth (Note 5) BW Code = 80H, 10pF load, VDD = +2.6V -90 MAX5386L/MAX5388L 600 MAX5386M/MAX5388M 150 MAX5386N/MAX5388N 75 2 _______________________________________________________________________________________ dB kHz Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers (VDD = +2.6V to +5.5V, VH_ = VDD, VL_ = GND, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VDD = +5V, TA = +25˚C. ) (Note 1) PARAMETER Total Harmonic Distortion Plus Noise SYMBOL THD+N Wiper Settling Time (Note 6) tS CONDITIONS MIN Measured at W, VH_ = 1VRMS at 1kHz TYP MAX 0.015 MAX5386L/MAX5388L 300 MAX5386M/MAX5388M 1000 MAX5386N/MAX5388N 2000 UNITS % ns POWER SUPPLIES Supply Voltage Range VDD Standby Current 2.6 Digital inputs = VDD or GND 5.5 1 V FA DIGITAL INPUTS Minimum Input High Voltage VIH Maximum Input Low Voltage VIL Input Leakage Current 70 %VDD -1 Input Capacitance 30 %VDD +1 FA 5 pF TIMING CHARACTERISTICS (Note 7) Maximum SCLK Frequency fMAX 10 MHz SCLK Clock Period tCP 100 ns SCLK Pulse-Width High tCH 40 ns SCLK Pulse-Width Low tCL 40 ns CS Fall to SCLK Rise Setup Time tCSS 40 ns SCLK Rise to CS Rise Hold Time DIN Setup Time tCSH 0 ns tDS 40 ns DIN Hold Time tDH 0 ns SCLK Rise to CS Fall Delay tCS0 10 ns SCLK Rise to SCLK Rise Hold Time tCS1 40 ns CS Pulse-Width High tCSW 100 ns Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design and characterization. Note 2: DNL and INL are measured with the potentiometer configured as a voltage-divider (Figure 1) with H = VDD and L = GND. The wiper terminal is unloaded and measured with an ideal voltmeter. Note 3: R-DNL and R-INL are measured with the potentiometer configured as a variable resistor (Figure 1). DNL and INL are measured with the potentiometer configured as a variable resistor. H_ is unconnected and L_ = GND. For VDD = +5V, the wiper terminal is driven with a source current of 400µA for the 10kI configuration, 80µA for the 50kI configuration, and 40µA for the 100kI configuration. For VDD = +2.6V, the wiper terminal is driven with a source current of 200µA for the 10kI configuration, 40µA for the 50kI configuration, and 20µA for the 100kI configuration. Note 4: The wiper resistance is the worst value measured by injecting the currents given in Note 3 in to W with L = GND. RW = (VW - VH)/IW. Note 5: Drive HA with a 1kHz GND to VDD amplitude tone. LA = LB = GND. No load. WB is at midscale with a 10pF load. Measure WB. Note 6: The wiper-settling time is the worst case 0 to 50% rise time, measured between tap 0 and tap 127. H = VDD, L = GND, and the wiper terminal is loaded with 10pF capacitance to ground. Note 7: Digital timing is guaranteed by design and characterization, not production tested. _______________________________________________________________________________________ 3 MAX5386/MAX5388 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VDD = 5V, TA = +25°C, unless otherwise noted.) SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE 0.2 VDD = 2.6V 0.001 0.0001 -40 -25 -10 0 20 35 50 65 80 95 110 125 TEMPERATURE (°C) 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 DIGITAL INPUT VOLTAGE (V) RESISTANCE (W TO L) vs. TAP POSITION (10kΩ) 55,000 50,000 W-TO-L RESISTANCE (kΩ) 9000 8000 7000 6000 5000 4000 3000 45,000 40,000 35,000 30,000 25,000 20,000 15,000 60k 50k 40k 30k 10k 0 0 150 130 VDD = 5V 110 90 70 102 153 TAP POSITION 204 0 255 0.10 153 204 IWIPER = 400µA 0.08 0.06 255 0.04 -0.1 50kI 100kI -0.3 0.02 0 -0.02 -0.04 -0.06 -0.4 -0.08 -0.10 -0.5 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 WIPER VOLTAGE 102 VARIABLE-RESISTOR DNL vs. TAP POSITION (10kI) MAX5386 toc08 10kI 0 -0.2 51 TAP POSITION DNL (LSB) WIPER RESISTANCE (Ω) 170 0.1 END-TO-END RESISTANCE % CHANGE VDD = 2.6V 190 51 END-TO-END RESISTANCE % CHANGE vs. TEMPERATURE MAX5386 toc07 210 0 0 WIPER RESISTANCE vs. WIPER VOLTAGE (10kΩ) 5.5 70k 20k 255 5.0 80k 5000 204 4.5 90k 1000 102 153 TAP POSITION 4.0 VDD (V) 100k 10,000 51 3.5 110k 2000 0 3.0 RESISTANCE (W-TO-L) vs. TAP POSITION (100kI) MAX5386 toc05 10,000 2.5 RESISTANCE (W TO L) vs. TAP POSITION (50kΩ) MAX5386 toc04 11,000 0.25 MAX5386 toc06 0 0.50 0.01 MAX5386 toc09 VDD = 2.6V 0.1 RESISTANCE (W-TO-L) (kI) 0.4 0.75 IDD (µA) 0.6 VDD = 5V 1 SUPPLY CURRENT (mA) VDD = 5V 1.00 MAX5386 toc02 0.8 SUPPLY CURRENT (µA) 10 MAX5386 toc01 1.0 SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX5386 toc03 SUPPLY CURRENT vs. TEMPERATURE W-TO-L RESISTANCE (kΩ) MAX5386/MAX5388 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (NC) 0 51 102 153 TAP POSITION 4 _______________________________________________________________________________________ 204 255 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers 0.6 0.2 0 -0.02 INL (LSB) 0.02 DNL (LSB) 0.4 0.02 0 -0.02 0 -0.2 -0.04 -0.04 -0.4 -0.06 -0.06 -0.6 -0.08 -0.08 -0.8 -0.10 -0.10 51 102 153 204 -1.0 0 51 102 153 204 255 0 153 204 TAP POSITION VARIABLE-RESISTOR INL vs. TAP POSITION (50kI) VARIABLE-RESISTOR INL vs. TAP POSITION (100kI) VOLTAGE-DIVIDER DNL vs. TAP POSITION (10kI) IWIPER = 400µA 0.4 0.10 0.3 0.08 0.06 0.1 0.02 0 -0.1 DNL (LSB) 0.04 0.1 INL (LSB) 0.2 0 -0.1 0 -0.02 -0.2 -0.2 -0.04 -0.3 -0.3 -0.06 -0.4 -0.4 -0.08 -0.5 -0.5 51 102 153 204 255 -0.10 0 51 102 153 204 255 0 51 102 153 204 TAP POSITION TAP POSITION TAP POSITION VOLTAGE-DIVIDER DNL vs. TAP POSITION (50kI) VOLTAGE-DIVIDER DNL vs. TAP POSITION (100kI) VOLTAGE-DIVIDER INL vs. TAP POSITION (10kI) 0.06 0.08 0.5 0.06 0.4 0.3 0.2 0.02 0.1 0 -0.02 INL (LSB) 0.04 0.02 DNL (LSB) 0.04 0 -0.02 0 -0.1 -0.04 -0.04 -0.2 -0.06 -0.06 -0.3 -0.08 -0.08 -0.4 -0.10 -0.10 51 102 153 TAP POSITION 204 255 255 MAX5386 toc18 0.08 MAX5386 toc17 0.10 MAX5386 toc16 0.10 255 MAX5386 toc15 0.5 0.2 0 102 TAP POSITION 0.3 0 51 TAP POSITION IWIPER = 80µA 0.4 255 MAX5386 toc14 0.5 INL (LSB) 0.06 IWIPER = 400µA 0.8 0.04 0 DNL (LSB) 1.0 0.04 MAX5386 toc13 DNL (LSB) 0.06 IWIPER = 400µA 0.08 VARIABLE-RESISTOR INL vs. TAP POSITION (10kI) MAX5386 toc12 IWIPER = 80µA 0.08 0.10 MAX5386 toc10 0.10 VARIABLE-RESISTOR DNL vs. TAP POSITION (100kI) MAX5386 toc11 VARIABLE-RESISTOR DNL vs. TAP POSITION (50kI) -0.5 0 51 102 153 TAP POSITION 204 255 0 51 102 153 204 255 TAP POSITION _______________________________________________________________________________________ 5 MAX5386/MAX5388 Typical Operating Characteristics (continued) (VDD = 5V, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VDD = 5V, TA = +25°C, unless otherwise noted.) VOLTAGE-DIVIDER INL vs. TAP POSITION (50kI) 0.3 0.2 0.2 0.1 0.1 VW-L 20mV/div 0 -0.1 -0.2 -0.2 -0.3 -0.3 -0.4 -0.4 -0.5 CS 5V/div -0.5 51 0 102 153 204 255 51 0 102 153 204 TAP POSITION TAP-TO-TAP SWITCHING TRANSIENT (CODE 128 TO 128) (MAX5386M) TAP-TO-TAP SWITCHING TRANSIENT (CODE 127 TO 128) (MAX5386N) MAX5386 toc22 MAX5386 POWER-ON WIPER TRANSIENT CODE 0 TO 128 MAX5386 toc23 MAX5386 toc24 VW-L 20mV/div VW-L 20mV/div CS 5V/div CS 5V/div 400ns/div CROSSTALK vs. FREQUENCY MAX5386M MAX5386N MAX5386 toc26 -80 MAX5386N MAX5386M -140 1 10 100 FREQUENCY (kHz) 1,000 10,000 MAX5386M 0.10 -60 -120 -30 0.12 MAX5386L -40 -100 -20 0.14 THD+N (%) CROSSTALK (dB) MAX5386L THD+N vs. FREQUENCY -20 0 0.1 VDD 2V/div 2µs/div 0 MAX5386 toc25 VIN = 1VP-P CW = 10pF 0.01 OUTPUT W 2V/div 1µs/div MIDSCALE FREQUENCY RESPONSE -10 200ns/div 255 TAP POSITION MAX5386 toc27 0 -0.1 MAX5386 toc20 0.4 INL (LSB) INL (LSB) 0.3 MAX5386 toc21 0.5 MAX5386 toc19 0.4 10 TAP-TO-TAP SWITCHING TRANSIENT (CODE 127 TO 128) (MAX5386L) VOLTAGE-DIVIDER INL vs. TAP POSITION (100kI) 0.5 GAIN (dB) MAX5386/MAX5388 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers 0.08 MAX5386N 0.06 0.04 MAX5386L 0.02 0 0.01 0.1 1 10 FREQUENCY (kHz) 100 1000 0.01 0.10 1 FREQUENCY (kHz) 6 _______________________________________________________________________________________ 10 100 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers PIN NAME FUNCTION 3 HB Resistor B High Terminal. The voltage at HB can be higher or lower than the voltage at LB. Current can flow in to or out of HB. 2 4 WB Resistor B Wiper Terminal 3 2 LB Resistor B Low Terminal. The voltage at LB can be higher or lower than the voltage at HB. Current can flow in to or out of LB. 4 — I.C. Internally Connected. Connect to GND. 5 1 GND Ground. Both pins must be grounded. 6, 7, 11, 13 — N.C. No Connection. Not internally connected. 8 5 Active-Low Chip-Select Input MAX5386 MAX5388 1 9 6 CS DIN 10 7 SCLK 12 8 VDD Power-Supply Input. Bypass VDD to GND with a 0.1µF capacitor close to the device. 14 — HA Resistor A High Terminal. The voltage at HA can be higher or lower than the voltage at LA. Current can flow in to or out of HA. 15 9 WA Resistor A Wiper Terminal 16 10 LA Resistor A Low Terminal. The voltage at LA can be higher or lower than the voltage at HA. Current can flow in to or out of LA. — — EP Exposed Pad (TQFN Only). Internally connected to GND. Connect to ground. Serial-Interface Data Input Serial-Interface Clock Input VOLTAGE-DIVIDER CONFIGURATION H VARIABLE-RESISTOR CONFIGURATION N.C. W W L L Figure 1. Voltage-Divider/Variable-Resistor Configurations _______________________________________________________________________________________ 7 MAX5386/MAX5388 Pin Description MAX5386/MAX5388 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers Detailed Description The MAX5386/MAX5388 dual, 256-tap, volatile low-voltage linear taper digital potentiometers offer three end-toend resistance values of 10kI, 50kI, and 100kI. Each potentiometer consists of 255 fixed resistors in series between terminals H and L. The potentiometer wiper, W, is programmable to access anyone of the 256 tap points on the resistor string. The potentiometers in each device are programmable independently of each other. The MAX5386/MAX5388 have an SPI interface. SPI Digital Interface The MAX5386/MAX5388 include an SPI interface, which provides a 3-wire write-only serial data interface to control the wiper tap position through inputs chip select (CS), data in (DIN), and data clock (SCLK). Drive CS low to load data from DIN synchronously into the serial shift register on the rising edge of each SCLK pulse. The MAX5386/MAX5388 load the last 9 bits of clocked data once CS transitions high. See Figures 2 and 3. After all the data bits are shifted in, data are latched into the appropriate potentiometer control register when CS goes from low to high. Data written to a memory register immediately updates the wiper position. Keep CS low during the entire data stream to prevent the data from being terminated. The first bit A0 (address bit) addresses one of the two potentiometers; writing a zero in A0 addresses control register A and writing a one in A0 addresses control register B. See Table 1. The power-on reset (POR) circuitry sets the wiper to midscale (D[7:0] 1000 0000). The 8 data bits (D7–D0) indicate the position of the wiper. For D[7:0] = 0000 0000, the wiper moves to the position closest to L. For D[7:0] = 1111 1111, the wiper moves closest to H. D[7:0] is 1000 0000 following poweron for both registers A and B. Register A: The data byte writes to register A, and the wiper of potentiometer A moves to the appropriate position at the rising edge of CS. D[7:0] indicates the position of the wiper. D[7:0] = 0000 0000 moves the wiper to the position closest to L. D[7:0] = 1111 1111 moves the wiper to the position closest to H. D[7:0] is 1000 0000 following power-on. Register B: The data byte writes to register B, and the wiper of potentiometer B moves to the appropriate position at the rising edge of CS. D[7:0] indicates the position of the wiper. D[7:0] = 0000 0000 moves the wiper to the position closest to L. D[7:0] = 1111 1111 moves the wiper to the position closest to H. D[7:0] is 1000 0000 following power-on. Table 1. SPI Register Map Bit Number 1 2 3 4 5 6 7 8 9 A0 D7 D6 D5 D4 D3 D2 D1 D0 Write Wiper Register A 0 D7 D6 D5 D4 D3 D2 D1 D0 Write Wiper Register B 1 D7 D6 D5 D4 D3 D2 D1 D0 Bit Name 8 _______________________________________________________________________________________ Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers WIPER REGISTER LOADED CS SCLK DIN A0 D7 D6 D5 D4 D3 D2 D0 D1 Figure 2. SPI Digital Interface Format tCSW CS tCS1 tCSO tCH tCSS tCL tCP tCSH tDH SCLK tDS DIN Figure 3. SPI Timing Diagram _______________________________________________________________________________________ 9 MAX5386/MAX5388 COMMAND STARTED 9 BITS MAX5386/MAX5388 Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers Applications Information Variable-Gain Amplifier Figure 4 shows a potentiometer adjusting the gain of a noninverting amplifier. Figure 5 shows a potentiometer adjusting the gain of an inverting amplifier. Adjustable Dual Linear Regulator Figure 6 shows an adjustable dual linear regulator using a dual potentiometer as two variable resistors. Adjustable Voltage Reference Figure 7 shows an adjustable voltage reference circuit using a potentiometer as a voltage-divider. VOUT1 OUT1 VOUT2 OUT2 VIN VOUT MAX8866 V+ IN H H L L W W L H W SET1 SET2 Figure 4. Variable-Gain Noninverting Amplifier Figure 6. Adjustable Dual Linear Regulator +5V H IN L VREF OUT W MAX6160 VIN H W VOUT GND Figure 5. Variable-Gain Inverting Amplifier L Figure 7. Adjustable Voltage Reference 10 ������������������������������������������������������������������������������������� Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers LCD Bias Control Figure 9 shows a positive LCD bias control circuit using a potentiometer as a voltage-divider. Programmable Filter Figure 10 shows a programmable filter using a dual potentiometer. Offset Voltage Adjustment Circuit Figure 11 shows an offset voltage adjustment circuit using a dual potentiometer. WB R3 VIN H W IS LB HB VOUT R3 R2 R1 R1 HA L VOUT R2 WA LA VOUT = IS x ((R3 x (1 + R2/R1)) + R2) Figure 8. Variable Gain I-to-V Converter Figure 10. Programmable Filter +5V WA +5V LA HA H W +30V VOUT VOUT L HB WB LB Figure 9. Positive LCD Bias Control Using a Voltage-Divider Figure 11. Offset Voltage Adjustment Circuit ______________________________________________________________________________________ 11 MAX5386/MAX5388 Variable Gain Current to Voltage Converter Figure 8 shows a variable gain current-to-voltage converter using a potentiometer as a variable resistor. Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers MAX5386/MAX5388 Functional Diagrams LA WA VDD HA MAX5386 256 DECODER HB SCLK LATCH SPI POR WB 256 DECODER DIN LATCH LB GND LA CS VDD WA MAX5388 HB 256 DECODER SCLK LATCH SPI POR WB 256 DECODER DIN LATCH LB GND CS Chip Information PROCESS: BiCMOS Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. PACKAGE TYPE PACKAGE CODE DOCUMENT NO. 10 µMAX U10+2 21-0061 16 TQFN-EP T1633-5 21-0136 12 ������������������������������������������������������������������������������������� Dual, 256-Tap, Volatile, Low-Voltage Linear Taper Digital Potentiometers REVISION NUMBER REVISION DATE 0 4/09 Initial release 1 11/09 Released MAX5386LATE+ and MAX5386NATE+ in Ordering Information; corrected specifications for Full-Scale Error, Zero-Scale Error, and Integral Nonlinearity in Electrical Characteristics; added I.C. row to Pin Description; corrected Figure 1 2 1/10 Released the MAX5388LAUB+, MAX5388MAUB+, MAX5388NAUB+ + in Ordering Information. DESCRIPTION PAGES CHANGED — 1, 2, 7 1 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products 13 Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX5386/MAX5388 Revision History