Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 General Description Benefits and Features The MAX5395 single, 256-tap volatile, low-voltage linear taper digital potentiometer offers three end-toend resistance values of 10k, 50k, and 100k. Potentiometer terminals are independent of supply for voltages up to 5.25V with single-supply operation from 1.7V to 5.5V (charge pump enabled). User-controlled shutdown modes allow the H, W, or L terminal to be opened with the wiper position set to zero-code, midcode, full-code, or the value contained in the wiper register. Ultra-low-quiescent supply current (< 1A) can be achieved for supply voltages between 2.6V and 5.5V by disabling the internal charge pump and not allowing potentiometer terminals to exceed the supply voltage by more than 0.3V. The MAX5395 provides a low 50ppm/C end-to-end temperature coefficient and features an I2C serial interface. Single Linear Taper 256-Tap Positions 10k, 50k, and 100k End-to-End Resistance 1.7V to 5.5V Extended Single Supply 0 to 5.25V H, W, L Operating Voltage Independent of VDD 1A (typ) Supply Current in Low-Power Mode 1.0 LSB INL, 0.5 LSB DNL (max) Wiper Accuracy Power-On Sets Wiper to Midscale 50ppm/C End-to-End Temperature Coefficient 5ppm/C Ratiometric Temperature Coefficient -40C to +125C Operating Temperature Range 2mm x 2mm, 8-Pin TDFN Package I2C-Compatible Serial Interface Applications The small package size, low operating supply voltage, low supply current, and automotive temperature range of the MAX5395 make the device uniquely suited for the portable consumer market and battery-backup industrial applications. The MAX5395 is available in a lead-free, 8-pin TDFN (2mm x 2mm) package. The device operates over the -40C to +125C automotive temperature range. Portable Electronics System Calibration Battery-Powered Systems Mechanical Potentiometer Replacement Ordering Information appears at end of data sheet. Typical Operating Circuit VDD 1.7V TO 5.5V (CHARGE PUMP ENABLED) H +5V VS MAX5395 ADDR0 SDA SCL MAX4250 W I2 C INTERFACE GND L R1 VO / VS = 1 + RMAX5395/R1 19-6393; Rev 3; 2/16 VO Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Absolute Maximum Ratings (All voltages referenced to GND.) VDD .........................................................................-0.3V to +6V H, W, L (charge pump enabled) ...........................-0.3V to +5.5V H, W, L (charge pump disabled)................... -0.3V to the lower of (VDD + 0.3V) or +6V ADDR0...................... -0.3V to the lower of (VDD + 0.3V) or +6V All Other Pins ..........................................................-0.3V to +6V Continuous Current into H, W, and L MAX5395L.........................................................................5mA MAX5395M........................................................................2mA MAX5395N........................................................................1mA Maximum Current into Any Input.........................................50mA Continuous Power Dissipation (TA = +70C) TDFN (derate 11.9mW/C above +70C)..................953.5mW Operating Temperature Range . ....................... -40C to +125C Storage Temperature Range............................ -65C to + 150C Junction Temperature.......................................................+150C Lead Temperature (soldering, 10s).................................+ 300C Soldering Temperature (reflow) . .....................................+260C 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. Package Thermal Characteristics (Note 1) TDFN Junction-to-Ambient Thermal Resistance (JA)........83.9C/W Junction-to-Ambient Thermal Resistance (JC)........37.0C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (VDD = 1.7V to 5.5V, VH = VDD, VL = GND, TA = -40C to +125C, unless otherwise noted. Typical values are at VDD = 1.8V, TA = +25C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS RESOLUTION 256-Tap Family N 256 Tap DC PERFORMANCE (Voltage-Divider Mode) Integral Nonlinearity (Note 3) INL Differential Nonlinearity DNL (Note 3) -1.0 +1.0 LSB -0.5 +0.5 LSB (DVW/VW)/DT, VH = VDD, VL = GND, No Load Ratiometric Resistor Tempco Charge pump enabled, 1.7V < VDD < 5.5V Full-Scale Error (Code FFh) Charge pump disabled, 2.6V < VDD < 5.5V 5 -0.5 MAX5395M MAX5395N -0.5 MAX5395L -1.0 LSB Charge pump enabled, 1.7V < VDD < 5.5V Zero-Scale Error (Code 00h) Charge pump disabled, 2.6V < VDD < 5.5V ppm/C +0.5 MAX5395M MAX5395N +0.5 MAX5395L +1.0 LSB DC PERFORMANCE (Variable Resistor Mode) Charge pump enabled, 1.7V < VDD < 5.5V Integral Nonlinearity (Note 4) R-INL Charge pump disabled, 2.6V < VDD < 5.5V Differential Nonlinearity R-DNL (Note 4) Wiper Resistance (Note 5) www.maximintegrated.com RWL -1.0 +1.0 MAX5395M MAX5395N -1.0 +1.0 MAX5395L -1.5 +1.5 -0.5 +0.5 Charge pump enabled, 1.7V < VDD < 5.5V Charge pump disabled, 2.6V < VDD < 5.5V 25 50 200 LSB LSB Maxim Integrated 2 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Electrical Characteristics (continued) (VDD = 1.7V to 5.5V, VH = VDD, VL = GND, TA = -40C to +125C, unless otherwise noted. Typical values are at VDD = 1.8V, TA = +25C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE (Resistor Characteristics) Terminal Capacitance CH, CL Measured to GND 10 Wiper Capacitance CW Measured to GND 20 pF End-to-End Resistor Tempco TCR No load 50 ppm/C End-to-End Resistor Tolerance Wiper not connected AC PERFORMANCE -3dB Bandwidth Total Harmonic Distortion Plus Noise BW THD+N (Note 6) tS (Note 7) Wiper Settling Time Charge-Pump Feedthrough at W Code = 80h, 10pF load, VDD = 1.8V -25 10k 50k 100k 10k 50k 100k VRW pF +25 % 1600 340 165 kHz 0.035 % 190 400 664 ns 600 nVRMS POWER SUPPLIES Supply Voltage Range VDD Terminal Voltage Range (H, W, L to GND) Supply Current (Note 8) IVDD 1.7 5.5 Charge pump enabled, 1.7V < VDD < 5.5V 0 5.25 Charge pump disabled, 2.6V < VDD < 5.5V 0 VDD Charge pump disabled, 1.7V 0.3 1.4 Charge pump disabled, 2.5V 0.4 1.7 Charge pump disabled, 5.5V 1.0 4.0 VDD = 5.5V 25 50 VDD = 1.7V 20 45 Charge pump enabled, 1.7V < VDD < 5.5V V V A DIGITAL INPUTS Minimum Input High Voltage VIH Maximum Input Low Voltage VIL 2.6V < VDD < 5.5V 70 1.7V < VDD < 2.6V 80 2.6V < VDD < 5.5V 30 1.7V < VDD < 2.6V 20 %x VDD +1 A Input Leakage Current -1 Input Capacitance ADDR0 Pullup/Pulldown Strength %x VDD RPURRPD (Note 9) 5 pF 60 k TIMING CHARACTERISTICS (Note 10) Maximum SCL Frequency Setup Time for START Condition www.maximintegrated.com fSCL tSU:STA 400 0.6 kHz s Maxim Integrated 3 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Electrical Characteristics (continued) (VDD = 1.7V to 5.5V, VH = VDD, VL = GND, TA = -40C to +125C, unless otherwise noted. Typical values are at VDD = 1.8V, TA = +25C.) (Note 2) PARAMETER Hold Time for START Condition SYMBOL CONDITIONS MIN TYP MAX UNITS tHD:STA 0.6 s SCL High Time tHIGH 0.6 s SCL Low Time tLOW 1.3 s Data Setup Time tSU:DAT 100 ns Data Hold Time tHD:DAT 0 s SDA, SCL Rise Time SDA, SCL Fall Time Setup Time for STOP Conditions tR tF 0.3 s 0.3 s tSU:STO 0.6 s Bus Free Time Between STOP and START Conditions tBUF 1.3 s Pulse-Suppressed Spike Width tSP 50 ns Capacitive Load for Each Bus CB 400 pF Note 2: Note Note Note Note Note Note Note Note All devices are production tested at TA = +25C and are guaranteed by design and characterization for TA = -40C to +125C. 3: DNL and INL are measured with the potentiometer configured as a voltage-divider with VH = 5.25V (QP enabled) or VDD (QP disabled) and VL = GND. The wiper terminal is unloaded and measured with an ideal voltmeter. 4: R-DNL and R-INL are measured with the potentiometer configured as a variable resistor (Figure 1). H is unconnected and L = GND. For charge pump enabled, VDD = 1.7V to 5.5V, the wiper terminal is driven with a source current of 400A for the 10k configuration, 80A for the 50k configuration, and 40A for the 100k configuration. For charge pump disabled and VDD = 5.5V, the wiper terminal is driven with a source current of 400A for the 10k configuration, 80A for the 50k configuration, and 40A for the 100k configuration. For charge pump disabled and VDD = 2.6V, the wiper terminal is driven with a source current of 200A for the 10k configuration, 40A for the 50k configuration, and 20A for the 100k configuration. 5: The wiper resistance is the maximum value measured by injecting the currents given in Note 4 into W with L = GND. RW = (VW - VH)/IW. 6: Measured at W with H driven with a 1kHz, 0V to VDD amplitude tone and VL = GND. Wiper at midscale with a 10pF load. 7: 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. 8: Digital Inputs at VDD or GND. 9: An unconnected condition on the ADDR0 pin is sensed via a pullup and pulldown operation. For proper operation, the ADDR0 pin should be tied to VDD, GND, or left unconnected with minimal capacitance. 10: Digital timing is guaranteed by design and characterization, and is not production tested. H N.C. W L W L Figure 1. Voltage-Divider and Variable Resistor Configurations www.maximintegrated.com Maxim Integrated 4 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Typical Operating Characteristics (VDD = 1.8V, TA = +25C, unless otherwise noted.) 25 20 15 10 5 -40 -25 -10 5 20 35 50 65 80 95 110 125 4 MAX5395 toc03 15 TA = -40C 10 5 0 5 5 4 3 2 1.70 2.65 3.60 4.55 5.50 40 35 30 25 20 15 10 5 0 0 96 128 160 192 224 256 100 MAX5395 toc06 45 1 64 MAX5395 toc05 50 90 W-TO-L RESISTANCE (k) 6 80 70 60 50 40 30 20 10 0 32 64 96 0 128 160 192 224 256 0 32 64 96 128 160 192 224 256 WIPER RESISTANCE vs. WIPER VOLTAGE WIPER RESISTANCE vs. WIPER VOLTAGE END-TO-END RESISTANCE PERCENTAGE CHANGE vs. TEMPERATURE WIPER RESISTANCE () VDD = 5V, QP OFF 40 35 VDD = 1.8V, QP ON 30 25 20 15 10 5 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 WIPER VOLTAGE (V) www.maximintegrated.com 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 WIPER VOLTAGE (V) 0.8 MAX5395 toc08 TAP POSITION END-TO-END RESISTANCE PERCENTAGE CHANGE (%) TAP POSITION MAX5395 toc07b TAP POSITION VDD = 2.6V, QP OFF 0 20 RESISTANCE (W-TO-L) vs. TAP POSITION (100k) MAX5395 toc07a W-TO-L RESISTANCE (k) WIPER RESISTANCE () 3 25 RESISTANCE (W-TO-L) vs. TAP POSITION (50k) 7 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 2 TA = +25C 30 RESISTANCE (W-TO-L) vs. TAP POSITION (10k) 8 32 1 0 VDD = 1.8V (LOW-HIGH) TA = +125C INPUT VOLTAGE (V) 9 0 VDD = 3.3V (HIGH-LOW) VDD = 1.8V (HIGH-LOW) 35 DIGITAL INPUT VOLTAGE (V) MAX5395 toc04 10 VDD = 5V (HIGH-LOW) SUPPLY CURRENT vs. INPUT VOLTAGE TEMPERATURE (C) W-TO-L RESISTANCE (k) 0 VDD = 5V (LOW-HIGH) VDD = 3.3V (LOW-HIGH) 40 SUPPLY CURRENT (A) SUPPLY CURRENT (A) 30 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 MAX5395 toc02 VDD = 1.8V 35 SUPPLY CURRENT (A) MAX5395 toc01 40 SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE SUPPLY CURRENT vs. TEMPERATURE 0.6 100k 0.4 0.2 0 -0.2 50k 10k -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) Maxim Integrated 5 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Typical Operating Characteristics (continued) (VDD = 1.8V, TA = +25C, unless otherwise noted.) TAP-TO-TAP SWITCHING TRANSIENT (CODE 127 TO 128, 10k) TAP-TO-TAP SWITCHING TRANSIENT (CODE 127 TO 128, 50k) MAX5395 toc09 MAX5395 toc10 VW-L 10mV/div VW-L 10mV/div VSCL 2V/div VSCL 2V/div VSCL 2V/div 200ns/div POWER-ON TRANSIENT (10k) 200ns/div POWER-ON TRANSIENT (50k) MAX5395 toc12a POWER-ON TRANSIENT (100k) MAX5395 toc12b MAX5395 toc12c VW-L 1V/div VW-L 1V/div VW-L 1V/div VDD 1V/div VDD 1V/div VDD 1V/div 10s/div 10s/div 10s/div MIDSCALE FREQUENCY RESPONSE (10k) MIDSCALE FREQUENCY RESPONSE (50k) MIDSCALE FREQUENCY RESPONSE (100k) -10 0 VDD = 5V -10 GAIN (dB) GAIN (dB) 0 MAX5395 toc15 10 MAX5395 toc14 MAX5395 toc13 10 0 GAIN (dB) MAX5395 toc11 VW-L 10mV/div 200ns/div 10 TAP-TO-TAP SWITCHING TRANSIENT (CODE 127 TO 128, 100k) VDD = 5V -10 VDD = 5V -20 -30 0.01k 0.1k -20 VDD = 1.8V VIN = 1VP-P CW = 10pF 1k 10k 100k FREQUENCY (Hz) www.maximintegrated.com 1M -20 VIN = 1VP-P CW = 10pF 10M -30 0.01k 0.1k VIN = 1VP-P CW = 10pF VDD = 1.8V 1k 10k 100k FREQUENCY (Hz) 1M 10M -30 0.01k 0.1k VDD = 1.8V 1k 10k 100k 1M 10M FREQUENCY (Hz) Maxim Integrated 6 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Typical Operating Characteristics (continued) (VDD = 1.8V, TA = +25C, unless otherwise noted.) TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY 0.16 900 800 VOLTAGE (nVRMS) 0.12 0.10 10k 50k 0.06 10k 600 500 400 300 200 0.04 100 100k 0.1 0.01 1 10 0 100 0.50 0.75 VARIABLE-RESISTOR DNL vs. TAP POSITION (10k) 0.3 0.3 0.1 DNL (LSB) 0.2 0.1 DNL (LSB) 0.2 0 0 -0.1 0 -0.2 -0.2 -0.3 -0.3 -0.3 -0.4 -0.4 -0.4 -0.5 -0.5 64 96 128 160 192 224 256 0.2 32 64 96 128 160 192 224 256 VARIABLE-RESISTOR INL vs. TAP POSITION (50k) VARIABLE-RESISTOR INL vs. TAP POSITION (100k) 0.5 0.4 0.3 INL (LSB) 0.1 0 -0.1 -0.2 -0.3 -0.3 VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 64 VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF 0.2 -0.2 32 0 VARIABLE-RESISTOR INL vs. TAP POSITION (10k) -0.1 0 -0.5 128 160 192 224 256 TAP POSITION 0 -0.5 96 TAP POSITION 0.1 -0.4 64 96 128 160 192 224 256 TAP POSITION www.maximintegrated.com VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 0.3 0.2 0.1 0 -0.1 -0.2 VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF -0.4 -0.5 0.5 INL (LSB) 0.3 32 TAP POSITION VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF 0.4 0 MAX5395 toc19b 32 2.00 -0.1 -0.2 0 1.75 VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 0.1 -0.1 1.50 VARIABLE-RESISTOR DNL vs. TAP POSITION (100k) 0.5 0.2 0.5 INL (LSB) VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 MAX5395 toc19a DNL (LSB) 0.3 0.5 MAX5395 toc18b VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 1.25 VARIABLE-RESISTOR DNL vs. TAP POSITION (50k) MAX5395 toc18a 0.5 1.00 FREQUENCY (MHz) FREQUENCY (kHz) MAX5395 toc18c 0.02 0 50k 100k 700 MAX5395 toc19c THD+N (%) 0.14 0.08 MAX5395 toc17 0.18 CHARGE-PUMP FEEDTHROUGH AT W 1000 MAX5395 toc16 0.20 0 32 64 96 128 160 192 224 256 TAP POSITION -0.3 -0.4 -0.5 0 32 64 96 128 160 192 224 256 TAP POSITION Maxim Integrated 7 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Typical Operating Characteristics (continued) (VDD = 1.8V, TA = +25C, unless otherwise noted.) 0.3 0.1 0.1 -0.1 DNL (LSB) 0.2 0.1 DNL (LSB) 0.2 0 0 -0.1 0 -0.1 -0.2 -0.2 -0.2 -0.3 -0.3 -0.3 -0.4 -0.4 -0.4 -0.5 -0.5 32 64 96 128 160 192 224 256 0.3 32 64 96 -0.5 128 160 192 224 256 64 96 128 160 192 224 256 TAP POSITION VOLTAGE-DIVIDER INL vs. TAP POSITION (10k) VOLTAGE-DIVIDER INL vs. TAP POSITION (50k) VOLTAGE-DIVIDER INL vs. TAP POSITION (100k) 0.5 VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 0.3 0.5 0.3 0.1 -0.1 INL (LSB) 0.2 0.1 INL (LSB) 0.2 0 0 -0.1 0 -0.1 -0.2 -0.2 -0.2 -0.3 -0.3 -0.3 -0.4 -0.4 -0.4 -0.5 -0.5 64 96 128 160 192 224 256 TAP POSITION www.maximintegrated.com 0 32 64 96 128 160 192 224 256 TAP POSITION VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 0.1 32 32 TAP POSITION 0.2 0 0 TAP POSITION VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 0 MAX5395 toc21b 0 VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 MAX5395 toc20c 0.3 0.5 0.2 0.5 INL (LSB) VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 MAX5395 toc21a DNL (LSB) 0.3 0.5 VOLTAGE-DIVIDER DNL vs. TAP POSITION (100k) MAX5395 toc21c VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF 0.4 MAX5395 toc20a 0.5 VOLTAGE-DIVIDER DNL vs. TAP POSITION (50k) MAX5395 toc20b VOLTAGE-DIVIDER DNL vs. TAP POSITION (10k) -0.5 0 32 64 96 128 160 192 224 256 TAP POSITION Maxim Integrated 8 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Pin Configuration TOP VIEW GND 2 ADDR0 3 8 H + L 1 7 W MAX5395 6 VDD EP SDA 4 5 SCL TDFN Pin Description PIN NAME FUNCTION 1 L Low Terminal. The voltage at L can be greater than or less than the voltage at H. Current can flow into or out of L. 2 GND 3 ADDR0 4 SDA I2C Serial Data Input 5 SCL I2C Clock Input 6 VDD Power Supply 7 W Wiper Terminal 8 H High Terminal. The voltage at H can be greater than or less than the voltage at L. Current can flow into or out of H. -- EP Exposed Pad. Internally connected to GND. Connect to ground. Ground Address Input 0. Connected to VDD, GND, or open. www.maximintegrated.com Maxim Integrated 9 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Functional Diagram MAX5395 L H GND W ADDRO SDA VDD I2C SCL INTERFACE Detailed Description The MAX5395 single, 256-tap volatile, low-voltage linear taper digital potentiometer offers three end-toend resistance values of 10k, 50k, and 100k. Potentiometer terminals are independent of supply for voltages up to +5.25V with single-supply operation from 1.7V to 5.5V (charge pump enabled). User-controlled shutdown modes allow the H, W, or L terminals to be opened with the wiper position set to zero-code, midcode, full-code, or the value contained in the wiper register. Ultralow-quiescent supply current (< 1A) can be achieved for supply voltages between 2.6V and 5.5V by disabling the internal charge pump and not allowing potentiometer terminals to exceed the supply voltage by more than 0.3V. The MAX5395 provides a low 50ppm/C end-to-end temperature coefficient and features a I2C serial interface. The small package size, low supply operating voltage, low supply current, and automotive temperature range of the MAX5395 make the device uniquely suited for the portable consumer market and battery-backup industrial applications. Charge Pump The MAX5395 contains an internal charge pump that guarantees the maximum wiper resistance, RWL, to be less than 50 (25 typ) for supply voltages down to 1.7V and allows pins H, W, and L to be driven between GND and 5.25V independent of VDD. Minimal chargepump feedthrough is present at the terminal outputs and is illustrated by the Charge-Pump Feedthrough at W vs. Frequency graph in the Typical Operating Characteristics. The charge pump is on by default but www.maximintegrated.com can be disabled with QP_OFF and enabled with the QP_ON commands (Table 1). The MAX5395 minimum supply voltage with charge pump disabled is limited to 2.6V and terminal voltage cannot exceed -0.3V to (VDD + 0.3V). I2C Interface The MAX5395 feature an I2C/SMBus-compatible, 2-wire serial interface consisting of a serial data line (SDA) and a serial clock line (SCL). SDA and SCL enable communication between the MAX5395 and the master at clock rates up to 400kHz. Figure 1 shows the 2-wire interface timing diagram. The master generates SCL and initiates data transfer on the bus. The master device writes data to the MAX5395 by transmitting the proper slave address followed by the command byte and then the data word. Each transmit sequence is framed by a START (S) or Repeated START (Sr) condition and a STOP (P) condition. Each word transmitted to the MAX5395 is 8 bits long and is followed by an acknowledge clock pulse. A master reading data from the MAX5395 must transmit the proper slave address followed by a series of nine SCL pulses for each byte of data requested. The MAX5395 transmit data on SDA in sync with the master-generated SCL pulses. The master acknowledges receipt of each byte of data. Each read sequence is framed by a START or Repeated START condition, a not acknowledge, and a STOP condition. SDA operates as both an input and an open-drain output. A pullup resistor, typically 4.7k, is required on SDA. SCL operates only as an input. A pullup resistor, typically 4.7k, is required on SCL if there are multiple masters on the bus, or if the single master has an open-drain SCL output. Series resistors in line with SDA and SCL are optional. Series resistors protect the digital inputs of the MAX5395 from high voltage spikes on the bus lines and minimize crosstalk and undershoot of the bus signals. The MAX5395 can accommodate bus voltages higher than VDD up to a limit of +5.5V. Bus voltages lower than VDD are not recommended and may result in significantly increased interface currents and data corruption. The MAX5395 with I2C interface contains a shift register that decodes the command and address bytes, routing the data to the register. Data written to a memory register immediately updates the wiper position. The wiper powers up in mid position, D[7:0] = 0x80 with charge pump enabled. Maxim Integrated 10 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 I2C START and STOP Conditions SDA and SCL idle high when the bus is not in use. A master initiates communication by issuing a START condition. A START condition is a high-to-low transition on SDA with SCL high. A STOP condition is a low-to-high transition on SDA while SCL is high (Figure 2). A START condition from the master signals the beginning of a transmission to the MAX5395. The master terminates transmission and frees the bus, by issuing a STOP condition. The bus remains active if a Repeated START condition is generated instead of a STOP condition. I2C Early STOP and Repeated START Conditions The MAX5395 recognizes a STOP condition at any point during data transmission except if the STOP condition occurs in the same high pulse as a START condition. For proper operation, do not send a STOP condition during the same SCL high pulse as the START condition. Transmissions ending in an early STOP condition will not impact the internal device settings. If the STOP occurs during a readback byte, the transmission is terminated and a later read mode request will begin transfer of the requested register data from the beginning. See Figure 3. It is possible to interrupt a transmission to a MAX5395 with a new START (Repeated START) condition (perhaps addressing another device), which leaves the input registers with data that has not been transferred to the internal registers. The unused data will not be stored under these conditions. The aborted MAX5395 I2C sequence will have no effect on the part. I2C Acknowledge In write mode, the acknowledge bit (ACK) is a clocked 9th bit that the MAX5395 uses to handshake receipt of each byte of data as shown in Figure 4. The MAX5395 pulls down SDA during the entire master-generated 9th clock pulse if the previous byte is successfully received. Monitoring ACK allows for detection of unsuccessful data transfers. An unsuccessful data transfer occurs if a receiving device is busy or if a system fault has occurred. In the event of an unsuccessful data transfer, the bus master will retry communication. tHD:STA SDA SCL tSU:STD tSU:DTA tSU:DAT tBUF tHD-DAT tLOW tHIGH tHD:STA tR tF REPEATED START CONDITION (Sr) START CONDITION (S) ACKNOWLEDGE (A) STOP CONDITION START CONDITION (P) (S) Figure 2. I2C Timing Diagram S Sr P P S S P P S P SCL SDA VALID START, REPEATED START, AND STOP PULSES INVALID START/STOP PULSE PAIRINGS-ALL WILL BE RECOGNIZED AS STARTS Figure 3. I2C START(s), Repeated START(S), and STOP(S) Conditions www.maximintegrated.com Maxim Integrated 11 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 In read mode, the master pulls down SDA during the 9th clock cycle to acknowledge receipt of data from the MAX5395. An acknowledge is sent by the master after each read byte to allow data transfer to continue. A notacknowledge is sent when the master reads the final byte of data from the MAX5395, followed by a STOP condition. I2C Slave Address Table 1. I2C Slave Address LSBs ADDR0 A1 A0 SLAVE ADDRESS GND 0 0 0101000 N.C. 0 1 0101001 VDD 1 1 0101011 The slave address is defined as the seven most significant bits (MSBs) followed by the R/W bit. See Figure 5 and Figure 6. The five most significant bits are 01010 with the 3 LSBs determined ADDR0 as shown in Table 1. Setting the R/W bit to 1 configures the MAX5395 for read mode. Setting the R/W bit to 0 configures the MAX5395 for write mode. The slave address is the first byte of information sent to the MAX5395 after the START condition. and data word. Each transmit sequence is framed by a START or Repeated START condition and a STOP condition as described above. Each word is 8 bits long and is always followed by an acknowledge clock (ACK) pulse as shown in Figure 5. The first byte contains the address of the MAX5395 with R/W = 0 to indicate a write. The second byte contains the command to be executed and the third byte contains the data to be written. The MAX5395 has the ability to detect an unconnected (N.C.) state on the ADDR0 input for additional address flexibility; if disconnecting the ADDR0 input, be certain to minimize all loading on the ADDR0 input (i.e. provide a landing for ADDR0, but do not allow any board traces). I2C Message Format for Readback Operations I2C Message Format for Writing A master device communicates with the MAX5395 by transmitting the proper slave address followed by command Each readback sequence is framed by a START or Repeated START condition and a STOP condition. Each word is 8 bits long and is followed by an acknowledge clock pulse as shown in Figure 6. The first byte contains the address of the MAX5395 with R/W = 0 to indicate a write. The second byte contains the register that is to be read back. There is a Repeated START condition, followed by the device address with R/W = 1 to indicate a CLOCK PULSE FOR ACKNOWLEDGMENT START CONDITION SCL 1 2 9 NOT ACKNOWLEDGE SDA ACKNOWLEDGE Figure 4. I2C Acknowledge WRITE ADDRESS START BYTE #1: I2C SLAVE ADDRESS SDA WRITE REGISTER BYTE #2: REG # = N WRITE DATA BYTE #3: DATA BYTE B[7:0] STOP 0 1 0 1 0 A1 A0 W A SEE REGISTER OPTIONS A D D D D D D D D A SCL ACK. GENERATED BY MAX5395L/ MAX5395M/MAX5395N ACK. GENERATED BY I2C MASTER REG N UPDATED Figure 5. I2C Complete Write Serial Transmission www.maximintegrated.com Maxim Integrated 12 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 read and an acknowledge clock. The master has control of the SCL line but the MAX5395 takes over the SDA line. The final byte in the frame contains the register data readback followed by a STOP condition. If additional bytes beyond those required to read back the requested data are provided, the MAX5395 will continue to read back ones. TSEL[1:0]: Tap select, 00- wiper is at contents of wiper register, 01 - wiper is at 0x00, 10 - wiper is at 0x80, 11 - wiper is at 0xFF. General Call Support The MAX5395 supports software reset through general call address 0x00 followed by R/W = 0, followed by 0x06 data. A software reset of the MAX5395 will return the part to the power-on default conditions. The MAX5395 will ACK the general call address and any command byte following, but will not support any general call features other than software reset. The wiper register and the configuration register are the only two registers that support readback (Table 2). Readback of all other registers is not supported and results in the readback of ones. D[7:0]: Wiper position QP: Charge pump status, 1 is enabled, 0 is disabled. HSW: H terminal switch status, 0 is closed, 1 is open WSW: W terminal switch status, 0 is closed, 1 is open LSW: L terminal switch status, 0 is closed, 1 is open Table 2. I2C READ Command Byte Summary REGISTER COMMAND BYTE DATA BYTE C7 C6 C5 C4 C3 C2 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0 WIPER 0 0 0 0 0 0 0 0 D7 D6 D5 D4 D3 D2 D1 D0 CONFIG 1 0 0 0 0 0 0 0 QP 0 0 HSW WRITE ADDRESS START BYTE #1: I2C SLAVE ADDRESS SDA WRITE COMMAND BYTE #2: COMMAND BYTE 0 1 0 1 0 A1 A0 W A SEE REGISTER OPTIONS A REPEATED READ ADDREESS START BYTE #3: I2C SLAVE ADDRESS LSW WSW READ DATA BYTE #4: DATA BYTE B[7:0] TSEL[1:0] STOP 0 1 0 1 0 A1 A0 R A D D D D D D D D ~A SCL ACK. GENERATED BY MAX5395L/ MAX5395M/MAX5395N ACK. GENERATED BY I2C MASTER Figure 6. Standard I2C Register Read Sequence www.maximintegrated.com Maxim Integrated 13 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Table 3. I2C Write Command Byte Summary COMMAND ADDRESS BYTE COMMAND BYTE DATA BYTE A6 A5 A4 A3 A2 A1 A0 R/W C7 C6 C5 C4 C3 C2 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0 WIPER 0 0 0 0 0 0 0 0 0 SD_CLR 0 1 0 0 0 0 0 0 0 SD_H_WREG 0 1 0 0 1 0 0 0 0 SD_H_ZERO 0 1 0 0 1 0 0 0 1 SD_H_MID 0 1 0 0 1 0 0 1 0 SD_H_FULL 0 1 0 0 1 0 0 1 1 0 A 1 0 0 0 1 0 0 0 A 0 1 0 0 0 1 0 0 1 SD_L_WREG S SD_L_ZERO See Table 1 SD_L_MID 0 1 0 0 0 1 0 1 0 SD_L_FULL 0 1 0 0 0 1 0 1 1 SD_W 0 1 0 0 0 0 1 X X QP_OFF 0 1 0 1 0 0 0 0 0 QP_ON 0 1 0 1 0 0 0 0 1 RST 0 1 1 0 0 0 0 0 0 WIPER Command The data byte writes to the wiper register and the potentiometer moves to the appropriate position. D[7:0] indicates the position of the wiper. D[7:0] = 0x00 moves the wiper to the position closest to L. D[7:0] = 0xFF moves the wiper closest to H. D[7:0] = 0x80 following power-on. SD_CLR Command Removes any existing shutdown condition. Connects all potentiometer terminals and returns the wiper to the value stored in the wiper register. The command does not affect the current status of the charge pump. SD_H_WREG Command Opens the H terminal and maintains the wiper at the wiper register location. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will close the H terminal and allow the wiper register to be written. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_H_ZERO Command Moves wiper to zero-scale position (0x00) and opens the H terminal. The wiper register remains unaltered. Writes cannot be made to the wiper register while shutdown www.maximintegrated.com D7 D6 D5 D4 D3 D2 D1 D0 A P Don't Care mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the H terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_H_MID Command Moves wiper to midscale position (0x80) and opens the H terminal. The wiper register remains unaltered. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the H terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_H_FULL Command Moves wiper to full-scale position (0xFF) and opens the H terminal. The wiper register remains unaltered. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the H terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. Maxim Integrated 14 MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer SD_L_WREG Command Opens the L terminal and maintains the wiper at the wiper register location. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will close the L terminal and allow wiper register to be written. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_L_ZERO Command Moves wiper to zero-scale position (0x00) and opens the L terminal. The wiper register remains unaltered. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the L terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_L_MID Command Moves wiper to midscale position (0x80) and opens the L terminal. The wiper register remains unaltered. Writes cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the L terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_L_FULL Command cannot be made to the wiper register while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close the L terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. SD_W Command Opens the W terminal keeping the internal tap position the same as the wiper register. Writes cannot be made to the wiper registers while shutdown mode is engaged. Clearing shutdown mode will return the wiper to the position contained in the wiper register and close W terminal. A RST will also deassert shutdown mode and return the wiper to midscale (0x80). This command does not affect the charge-pump status. QP_OFF Command Disables the onboard charge pump and places device in low power mode. Low supply voltage is limited to 2.6V. QP_ON Command Enables the onboard charge pump to allow low-supply voltage operation. This is the power-on default condition. Low supply voltage is 1.7V. RST Command Returns the device to power-on default conditions. Resets the wiper register to midscale (0x80), enables charge pump, and deasserts any shutdown modes. Moves wiper to full-scale position (0xFF) and opens the L terminal. The wiper register remains unaltered. Writes www.maximintegrated.com Maxim Integrated 15 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Ordering Information PIN-PACKAGE INTERFACE TAPS END-TO-END RESISTANCE (k) MAX5395LATA+T 8 TDFN-EP* I2C 256 10 MAX5395MATA+T 8 TDFN-EP* I2C 256 50 MAX5395NATA+T 8 TDFN-EP* I2C 256 100 PART Note: All devices operate over the -40C to +125C temperature range. +Denotes a lead(Pb)-free/RoHS-compliant package. T = Tape and reel. *EP = Exposed pad. Chip Information PROCESS: BiCMOS www.maximintegrated.com Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 TDFN-EP T822+2 21-0168 90-0065 Maxim Integrated 16 Single, 256-Tap Volatile, I2C, Low-Voltage Linear Taper Digital Potentiometer MAX5395 Revision History REVISION NUMBER REVISION DATE 0 7/12 Initial release -- 1 9/12 Revised the Absolute Maximum Ratings 2 2 11/14 Removed automotive references from data sheet 3 2/16 Add charge pump current at various disabled conditions DESCRIPTION PAGES CHANGED 1, 10 3 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated's website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. (c) 2016 Maxim Integrated Products, Inc. 17