Datasheet MAX5527, MAX5528, MAX5529 (Maxim) - 7

One-Time Programmable, Linear-Taper Digital Potentiometers MAX5527/MAX5528/MAX5529 Pin Description PIN NAME FUNCTION
1 W Wiper Connection Chip-Select Input. A high-to-low CS transition determines the increment/decrement mode. Increment 2 CS if U/D is high, or decrement if U/D is low. CS is also used for one-time programming. See the PV One- Time Programming section. 3 VDD Supply Voltage. Bypass with a 0.1µF capacitor to GND. 4 GND Ground One-Time Programming Voltage. Connect PV to an 11V supply at the time the device is 5 PV programmed/locked, and bypass with a 22µF capacitor to GND. For normal operation, connect to GND or leave floating. 6 U/D Up/Down Control Input. When CS is low, a low-to-high transition at U/D increments or decrements the wiper position. See the Digital Interface Operation section. 7 L Resistor Low Terminal 8 H Resistor High Terminal Exposed Pad (TDFN Only). Internally connected to GND. Connect to a large ground plane to — EP maximize thermal dissipation.
Detailed Description
The MAX5527/MAX5528/MAX5529 100kΩ/50kΩ/10kΩ POTENTIOMETER VARIABLE-RESISTOR end-to-end resistance digitally-controlled potentiome- CONFIGURATION CONFIGURATION ters offer 64 wiper tap positions accessible along the H H resistor array between H and L. These devices function as potentiometers or variable resistors (see Figure 1). W The wiper (W) position is adjusted sequentially through W the tap positions using a simple 2-wire up/down inter- face. These digital potentiometers provide an optional one-time programmable feature that sets and locks the L L power-on reset position of the wiper (see the PV One- Time Programming section). Once the desired wiper position is programmed, the 2-wire interface can be Figure 1. Potentiometer/Variable-Resistor Configuration disabled to prevent unwanted adjustment. mode is set, the device remains in that mode until CS
Digital Interface Operation
goes high. The MAX5527/MAX5528/MAX5529 provide two modes Idle U/D high for normal operation. If U/D is low when of operation when the serial interface is active: incre- CS transitions low to high, the wiper moves one addi- ment mode or decrement mode. The serial interface is tional tap in its present direction. The wiper remains in only active when CS is low. the same position when U/D is high and CS transitions The CS and U/D inputs control the position of the wiper low to high. After CS returns high, the wiper position along the resistor array. Set U/D high to increment the remains the same (Figure 4). MAX5527/MAX5528/MAX5529 when CS transitions Additional increments do not change the wiper position from high to low (Figure 2). Set U/D low to decrement when the wiper is at the maximum end of the resistor the MAX5527/MAX5528/MAX5529 when CS transitions array. Additional decrements do not change the wiper high to low (Figure 3). Once CS is held low, each low- position when the wiper is at the minimum end of the to-high transition at U/D increments or decrements the resistor array. wiper one position. Once the increment or decrement
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