MAX5402 19-1896 Rev 0 1/01 256-Tap, PoT, Low-Drift, Digital Potentiometer General Description Features The MAX5402 PoT digital potentiometer is a 256-tap Small Footprint, 8-Pin MAX Package variable resistor with 10k total resistance in a tiny 8- Ultra-Low 100nA Supply Current pin MAX package. This device functions as a mechan- ical potentiometer, consisting of a fixed resistor string +2.7V to +5.5V Single-Supply Operation with a digitally controlled wiper contact. It operates 256 Tap Positions from +2.7V to +5.5V single-supply voltages and uses an ultra-low 0.1A supply current. This device also pro- Low Ratiometric Temperature Coefficient vides glitchless switching between resistor taps, as well 5ppm/C as a convenient power-on reset (POR) that sets the Low End-to-End Resistor Temperature Coefficient wiper to the midscale position at power-up. A low 5ppm/C ratiometric temperature coefficient makes it 35ppm/C ideal for applications requiring low drift. Power-On Reset: Wiper Goes to Midscale The MAX5402 serves well in applications requiring digi- (Position 128) tally controlled resistors, including adjustable voltage Glitchless Switching Between the Resistor Taps references and programmable gain amplifiers (PGAs). A nominal end-to-end resistor temperature coefficient of 3-Wire SPI-Interface Compatible 35ppm/C makes this part suitable for use as a variable 10k Resistor Value resistor in applications such as low-tempco adjustable gain and other circuit configurations. This device is guaranteed over the extended industrial temperature range (-40C to +85C). Applications Ordering Information Mechanical Potentiometer Replacement TEMP. PIN- PART R (k ) RANGE PACKAGE Low-Drift PGAs Adjustable Voltage References MAX5402EUA -40C to +85C 8 MAX 10 PoT is a trademark of Maxim Integrated Products. SPI is a trademark of Motorola, Inc. Functional Diagram Pin Configuration V DD TOP VIEW H R R 256 8 8 8-BIT L 1 8 H DECODE W 8-BIT LATCH SHIFT GND 2 7 W REGISTER L DIN MAX5402 CS 3 6 V DD MAX5402 DIN 4 5 SCLK SCLK POR CLOCK LOGIC CS MAX GND Maxim Integrated Products 1 For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.256-Tap, PoT, Low-Drift, Digital Potentiometer ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Operating Temperature Range ...........................-40C to +85C DD DIN, SCLK, CS to GND ............................................-0.3V to +6V Junction Temperature......................................................+150C H, L, W to GND.............................................-0.3V to (V + 0.3) Storage Temperature Range .............................-65C to +150C DD Maximum Continuous Current into Pins H, L, and W ...........1mA Lead Temperature (soldering, 10s) .................................+300C Continuous Power Dissipation (T = +70C) A 8-Pin MAX (derate 4.1mW/C above +70C) ............330mW 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 = +5V, V = V , V = 0, T = T to T . Typical values are at V = +5V, T = +25C, unless otherwise noted.) DD H DD L A MIN MAX DD A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE (Voltage-Divider Mode) Resolution N 8 Bits Integral Nonlinearity (Notes 1, 2) INL 1/2 LSB Differential Nonlinearity DNL 1 LSB (Notes 1, 2) End-to-End Resistor Tempco TC 35 ppm/C R Ratiometric Resistor Tempco 5 ppm/C Full-Scale Error -6 LSB Zero-Scale Error +6 LSB DC PERFORMANCE (Variable-Resistor Mode) Resolution N 8 Bits V = +5V 1 LSB DD Integral Nonlinearity INL (Notes 1, 3) V = +3V 3 LSB DD V = +5V 1/2 LSB Differential Nonlinearity DD DNL (Notes 1, 3) V = +3V 1/2 LSB DD DC PERFORMANCE (Resistor Characteristics) V = +5V 275 DD Wiper Resistance (Note 4) R W V = +3V 550 DD Wiper Capacitance C 46 pF W End-to-End Resistance R 7.5 10 12.5 k HL DIGITAL INPUTS Input High Voltage V 0.7 V V IH DD Input Low Voltage V 0.3 V V IL DD Input Leakage Current 1.0 A Input Capacitance 5pF TIMING CHARACTERISTICS (ANALOG) Wiper-Settling Time t To 50% of fina l val ue from code 0 to code 128 100 ns S TIMING CHARACTERISTICS (DIGITAL) (Note 5) (Figure 2) SCLK Clock Period t 100 ns CP SCLK Pulse Width High t 40 ns CH 2 MAX5402