DATASHEET X9251 FN8166 Rev 7.00 Single Supply/Low Power/256-Tap/SPI Bus, Quad Digitally-Controlled (XDCP) January 14, 2021 Potentiometer The X9251 integrates four digitally controlled potentiometers Features (XDCP) on a monolithic CMOS integrated circuit. Four potentiometers in one package The digitally controlled potentiometers are implemented with 256 resistor taps0.4% resolution a combination of resistor elements and CMOS switches. The position of the wipers are controlled by the user through the SPI serial interface for write, read, and transfer operations of SPI bus interface. Each potentiometer has associated with it a the potentiometer volatile Wiper Counter Register (WCR) and four nonvolatile Wiper resistance: 100 typical at V = 5V CC Data Registers that can be directly written to and read by the 4 Nonvolatile data registers for each potentiometer user. The content of the WCR controls the position of the wiper. At power-up, the device recalls the content of the default Data Nonvolatile storage of multiple wiper positions Registers of each DCP (DR00, DR10, DR20, and DR30) to the Standby current <5A max corresponding WCR. V : 2.7V to 5.5V operation CC The XDCP can be used as a three terminal potentiometer or as 50k version of total resistance a two terminal variable resistor in a wide variety of applications including control, parameter adjustments, and 100 year data retention signal processing. Single supply version of X9250 Endurance: 100,000 data changes per bit per register 24 Ld TSSOP Low power CMOS Pb-free (RoHS compliant) R R V R R H0 H1 H2 H3 CC HOLD DCP0 DCP1 DCP2 DCP3 WCR1 WCR2 WCR3 WCR0 DR10 DR20 DR30 A1 DR00 SPI DR11 DR31 Interface DR01 DR21 POWER UP, A0 DR02 DR12 DR22 DR32 INTERFACE DR13 DR23 DR33 DR03 CONTROL SO AND STATUS SI SCK CS V SS R R R R R R R WP R L1 L3 W0 L0 W1 W2 L2 W3 FIGURE 1. FUNCTIONAL DIAGRAM FN8166 Rev 7.00 Page 1 of 20 January 14, 2021X9251 Circuit Level Applications System Level Applications Vary the gain of a voltage amplifier Adjust the contrast in LCD displays Provide programmable DC reference voltages for comparators Control the power level of LED transmitters in communication and detectors systems Control the volume in audio circuits Set and regulate the DC biasing point in an RF power amplifier in wireless systems Trim out the offset voltage error in a voltage amplifier circuit Control the gain in audio and home entertainment systems Set the output voltage of a voltage regulator Provide the variable DC bias for tuners in RF wireless systems Trim the resistance in Wheatstone bridge circuits Set the operating points in temperature control systems Control the gain, characteristic frequency and Q-factor in filter circuits Control the operating point for sensors in industrial systems Set the scale factor and zero point in sensor signal Trim offset and gain errors in artificial intelligent systems conditioning circuits Vary the frequency and duty cycle of timer ICs Vary the DC biasing of a pin diode attenuator in RF circuits Provide a control variable (I, V, or R) in feedback circuits FN8166 Rev 7.00 Page 2 of 20 January 14, 2021