MAX5422/MAX5423/MAX5424 19-3371 Rev 0 7/04 256-Tap, Nonvolatile, SPI-Interface, Digital Potentiometers General Description Features The MAX5422/MAX5423/MAX5424 nonvolatile, linear- Wiper Position Stored in Nonvolatile Memory taper, digital potentiometers perform the function of a (EEPROM) and Recalled Upon Power-Up or mechanical potentiometer, but replace the mechanics Interface Command with a simple 3-wire SPI-compatible digital interface. Each device performs the same function as a discrete 3mm x 3mm x 0.8mm TDFN Package potentiometer or variable resistor and has 256 tap points. 35ppm/C End-to-End Resistance Temperature The devices feature an internal, nonvolatile EEPROM used to store the wiper position for initialization during Coefficient power-up. The 3-wire SPI-compatible serial interface 5ppm/C Ratiometric Temperature Coefficient allows communication at data rates up to 5MHz, mini- mizing board space and reducing interconnection com- 50k, 100k, and 200k Resistor Values plexity in many applications. 5MHz SPI-Compatible Serial Interface The MAX5422/MAX5423/MAX5424 provide three nomi- nal resistance values: 50k (MAX5422), 100k 500nA (typ) Static Supply Current (MAX5423), or 200k (MAX5424). The nominal resistor temperature coefficient is 35ppm/C end-to-end and Single-Supply Operation: +2.7V to +5.25V only 5ppm/C ratiometric. This makes the devices ideal 256 Tap Positions for applications requiring a low-temperature-coefficient variable resistor, such as low-drift, programmable gain- 0.5 LSB DNL in Voltage-Divider Mode amplifier circuit configurations. The MAX5422/MAX5423/MAX5424 are available in a 0.5 LSB INL in Voltage-Divider Mode 3mm x 3mm 8-pin TDFN package, and are specified over the extended -40C to +85C temperature range. SPI is a trademark of Motorola, Inc. Applications Mechanical Potentiometer Replacement Pin Configuration Low-Drift Programmable Gain Amplifiers TOP VIEW Audio Volume Control Liquid-Crystal Display (LCD) Contrast Control Low-Drift Programmable Filters V 1 8 H DD Functional Diagram SCLK 2 7 W MAX5422 DIN MAX5423 3 6 L H MAX5424 CS 45 GND 8-BIT 256- 256 8 8 8-BIT SHIFT W POSITION V DD LATCH REGISTER DECODER GND TDFN (3mm x 3mm) L CS POR MAX5422 SPI 8-BIT SCLK MAX5423 INTERFACE NV MEMORY MAX5424 DIN Ordering Information/Selector Guide END-TO-END PART TEMP RANGE PIN-PACKAGE TOP MARK RESISTANCE (k) 8 TDFN-EP* MAX5422ETA -40C to +85C50 AIJ 8 TDFN-EP* MAX5423ETA -40C to +85C 100 AII 8 TDFN-EP* MAX5424ETA -40C to +85C 200 AIH *EP = Exposed pad. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE256-Tap, Nonvolatile, SPI-Interface, Digital Potentiometers ABSOLUTE MAXIMUM RATINGS V to GND...........................................................-0.3V to +6.0V Continuous Power Dissipation (T = +70C) DD A All Other Pins to GND.................................-0.3V to (V + 0.3V) 8-Pin TDFN (derate 24.4mW/C above +70C) .........1951mW DD Maximum Continuous Current into H, L, and W Operating Temperature Range ...........................-40C to +85C MAX5422......................................................................1.3mA Junction Temperature......................................................+150C MAX5423......................................................................0.6mA Storage Temperature Range .............................-60C to +150C MAX5424......................................................................0.3mA Lead Temperature (soldering, 10s) .................................+300C 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 (V = +2.7V to +5.25V, H = V , L = GND, T = -40C to +85C. Typical values are at V = +5.0V, T = +25C, unless otherwise noted.) DD DD A DD A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE (VOLTAGE-DIVIDER MODE) Resolution N 256 Taps Integral Nonlinearity INL (Note 1) 0.5 LSB Differential Nonlinearity DNL (Note 1) 0.5 LSB End-to-End Resistance TC 35 ppm/C R Temperature Coefficient Ratiometric Resistance 5 ppm/C Temperature Coefficient MAX5422 -0.6 Full-Scale Error MAX5423 -0.3 LSB MAX5424 -0.15 MAX5422 0.7 Zero-Scale Error MAX5423 0.35 LSB MAX5424 0.18 DC PERFORMANCE (VARIABLE-RESISTOR MODE) V = 3V 3.0 Integral Nonlinearity DD INL LSB (Note 2) V = 5V 1.5 DD V = 3V, MAX5422, -40C T +85C, DD A -1.0 +2.0 guaranteed monotonic V = 3V, MAX5422, 0C T +85C, DD A -1.0 +1.2 Differential Nonlinearity guaranteed monotonic DNL LSB (Note 2) V = 3V, MAX5423 1.0 DD V = 3V, MAX5424 1.0 DD V = 5V 1.0 DD DC PERFORMANCE (RESISTOR CHARACTERISTICS) Wiper Resistance R V = 3V to 5.25V (Note 3) 325 675 W DD Wiper Capacitance C 10 pF W MAX5422 37.5 50 62.5 End-to-End Resistance MAX5423 75 100 125 k MAX5424 150 200 250 2 MAX5422/MAX5423/MAX5424