APPLICATION NOTE A V A I L A B L E AN99, AN115, AN120, AN124, AN133, AN134, AN135 Low Noise, 32 Taps X9316 Digitally-Controlled (XDCP) Potentiometer FEATURES DESCRIPTION Solid-State Potentiometer The Xicor X9316 is a digitally-controlled (XDCP) Three-Wire Serial Interface potentiometer. The device consists of a resistor array, Low Noise wiper switches, a control section, and nonvolatile 32 Wiper Tap Points memory. The wiper position is controlled by a three- Wiper position stored in nonvolatile memory wire interface. and recalled on power-up The potentiometer is implemented by a resistor array 31 Resistive Elements composed of 31 resistive elements and a wiper Temperature compensated switching network. Between each element and at End to end resistance range 20% either end are tap points accessible to the wiper Terminal voltages, -5V to +5V terminal. The position of the wiper element is Low Power CMOS controlled by the CS, U/D, and INC inputs. The V = 5V CC position of the wiper can be stored in nonvolatile Active current, 3mA max. memory and then be recalled upon a subsequent Standby current, 1A max. power-up operation. High Reliability Endurance, 100,000 data changes per bit The device can be used as a three-terminal Register data retention, 100 years potentiometer or as a two-terminal variable resistor in R Values = 1K , and 10K a wide variety of applications including: TOTAL Packages control 14-lead SOIC and DIP parameter adjustments signal processing BLOCK DIAGRAM U/D 5-Bit R /V 31 H H INC Up/Down V V+ CS Counter CC 30 29 R /V Up/Down H H (U/D) 5-Bit 28 Control One Increment Nonvolatile R /V and W W of (INC) Memory Memory Thirty Two Transfer Device Select Resistor Decoder Gates (CS) Array R /V L L 2 V V SS Store and 1 Recall Control General Circuitry 0 R /V L L V+ R /V W W V- V CC Detailed V SS XDCP is a trademark of Xicor, Inc. Characteristics subject to change without notice. 1 of 10 REV 1.1.2 10/15/00 www.xicor.com X9316 PIN DESCRIPTIONS V+, V (Analog positive/negative power supply) V+ and V are the analog supply voltages for the R /V and R /V H H L L XDCP. The high (R /V ) and low (R /V ) terminals of the H H L L X9316 are equivalent to the xed terminals of a PIN CONFIGURATION mechanical potentiometer. The minimum voltage is V and the maximum is V+. The terminology of R /V and L L 14-Lead DIP/SOIC R /V references the relative position of the terminal H H NC NC 1 14 in relation to wiper movement direction selected by the V INC 2 13 CC U/D input and not the voltage potential on the terminal. U/D 3 12 CS R V R V 4 11 H H X9316 L L R /V W W V 5 10 SS R V W W R /V is the wiper terminal and is equivalent to the W w V- 9 V+ 6 movable terminal of a mechanical potentiometer. The NC 8 7 NC position of the wiper within the array is determined by the control inputs. The wiper terminal series resistance is typically 100 . PIN NAMES Up/Down (U/D) Symbol Description The U/D input controls the direction of the wiper R /V High Terminal H H movement and whether the counter is incremented or R /V Wiper Terminal W W decremented. R /V Low Terminal L L Increment (INC) V Ground SS The INC input is negative-edge triggered. Toggling V Digital Supply Voltage CC INC will move the wiper and either increment or U/D Up/Down Control Input decrement the counter in the direction indicated by the INC Increment Control Input logic level on the U/D input. CS Chip Select Control Input Chip Select (CS) V+ Positive Analog Voltage The device is selected when the CS input is LOW. The V Negative Analog Voltage current counter value is stored in nonvolatile memory NC No Connection when CS is returned HIGH while the INC input is also HIGH. After the store operation is complete the X9316 will be placed in the low power standby mode until the device is selected once again. Characteristics subject to change without notice. 2 of 10 REV 1.1.2 10/15/00 www.xicor.com