Single, 128-Tap, Low Voltage Digitally Controlled Potentiometer (XDCP) ISL23418 Features 128 Resistor Taps The ISL23418 is a volatile, low voltage, low noise, low power, SPI bus, 128 taps, single digitally controlled potentiometer SPI Serial Interface (DCP), which integrates DCP core, wiper switches, and control - No Additional Level Translator for Low Bus Supply logic on a monolithic CMOS integrated circuit. - Daisy Chaining of Multiple DCP The digitally controlled potentiometer is implemented with a Wiper Resistance: 70 Typical V = 3.3V CC combination of resistor elements and CMOS switches. The position of the wiper is controlled by the user through the SPI Shutdown Mode: Forces DCP into End-to-end Open Circuit bus interface. The potentiometer has an associated volatile RW Shorted to RL Internally Wiper Register (WR) that can be directly written to and read by Power-on Preset to Mid-scale (64-tap Position) the user. The contents of the WR controls the position of the Shutdown and Standby Current <2.8A Max wiper. When powered on, the ISL23418 wiper always commences at mid-scale (64-tap position). Power Supply -V = 1.7V to 5.5V Analog Power Supply The low voltage, low power consumption, and small package CC -V = 1.2V to 5.5V SPI Bus/Logic Power Supply size of the ISL23418 make it an ideal choice for use in battery LOGIC operated equipment. The ISL23418 has a V pin allowing LOGIC DCP Terminal Voltage from 0V to V CC down to 1.2V bus operation, independent from the V value. CC 10k, 50k or 100k Total Resistance This allows for low logic levels to be connected directly to the ISL23418 without passing through a voltage level shifter. Extended Industrial Temperature Range: -40C to +125C The DCP can be used as a three-terminal potentiometer or as a 10 Ld MSOP or 10 Ld TQFN Packages two-terminal variable resistor in a wide variety of applications Pb-free (RoHS compliant) including control, parameter adjustments, and signal processing. Applications Power Supply Margining Related Literature RF Power Amplifier Bias Compensation See ISL23415, Single, Low Voltage Digitally Controlled Potentiometer (XDCP) LCD Bias Compensation Gain Adjustment in Battery Powered Instruments Portable Medical Equipment Calibration 10000 V REF 8000 6000 RH1 - V REF M 4000 RW1 ISL23418 + ISL28114 2000 RL1 0 0 25 50 75 100 125 TAP POSITION (DECIMAL) FIGURE 1. FORWARD AND BACKWARD RESISTANCE vs TAP FIGURE 2. V ADJUSTMENT REF POSITION, 10k August 3, 2011 CAUTION: These devices are sensitive to electrostatic discharge follow proper IC Handling Procedures. 1 1-888-INTERSIL or 1-888-468-3774 Copyright Intersil Americas Inc. 2011. All Rights Reserved FN7901.0 XDCP is a trademark of Intersil Americas Inc. Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries .All other trademarks mentioned are the property of their respective owners. RESISTANCE ( )ISL23418 Block Diagram V V CC LOGIC RH SCK POWER-UP INTERFACE, SDI I/O BLOCK LEVEL CONTROL WR SDO SHIFTER AND VOLATILE STATUS CS REGISTER LOGIC AND WIPER CONTROL CIRCUITRY RL RW GND Pin Configurations Pin Description ISL23418 MSOP TQFN SYMBOL DESCRIPTION (10 LD MSOP) 110 V SPI bus/logic supply range 1.2V to TOP VIEW LOGIC 5.5V O 10 GND V 1 LOGIC 2 1 SCK Logic pin: serial bus clock input SCK 2 V 9 CC 3 2 SDO Logic pin: serial bus data output RH SDO 3 8 (configurable) 7 SDI 4 RW 4 3 SDI Logic pin: serial bus data input CS RL 5 6 54 CS Logic pin: active low Chip Select 65 RL DCP low terminal ISL23418 (10 LD TQFN) 76 RW DCP wiper terminal TOP VIEW 8 7 RH DCP high terminal 98 V Analog power supply range 1.7V to CC 5.5V O SCK 1 9 GND 10 9 GND Ground pin SDO 2 8 V CC SDI 3 7 RH CS 4 6 RW FN7901.0 2 August 3, 2011 RL 5 10 V LOGIC