X9421 Xicor, X9421 Datasheet
X9421
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X9421 Summary of contents
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... Interface & bus interface REV 1.1.6 8/1/02 X9421 DESCRIPTION The X9421 integrates a single digitally controlled potentiometer integrated circuit. The digital controlled potentiometer is implemented using 63 resistive elements in a series array. Between each element are tap points connected to the wiper terminal through switches. The position of the wiper on the array is controlled by the user through the SPI bus interface ...
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... X9421 DETAILED FUNCTIONAL DIAGRAM V CC HOLD CS INTERF A CE SCK AND SO CONTROL CIRCUITR CIRCUIT LEVEL APPLICATIONS • Vary the gain of a voltage amplifier • Provide programmable dc reference voltages for comparators and detectors • Control the volume in audio circuits • ...
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... Low Terminal of the Potentiometer System Supply Voltage Connect NC No Connect NC No Connect www.xicor.com SOIC X9421 HOLD Brief Description Characteristics subject to change without notice ...
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... The SCK input is used to clock data into and out of the X9421. Chip Select (CS) When CS is HIGH, the X9421 is deselected and the SO pin is at high impedance, and (unless an internal write cycle is underway) the device will be in the standby state. CS LOW enables the X9421, placing it in the active power mode ...
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... Finally loaded with the contents of its data register zero (DR0) upon power-up. The Wiper Counter Register is a volatile register; that is, its contents are lost when the X9421 is powered- down. Although the register is automatically loaded with the value in DR0 upon power-up, this may be different from the value present at power-down ...
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... WIP bit is read with a Read Status command. INSTRUCTIONS Address/Identification (ID) Byte The first byte sent to the X9421 from the host, following a CS going HIGH to LOW, is called the Address or Identification byte. The most significant four bits of the slave address are a device type identifier, for the X9421 this is fi ...
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... These instructions transfer data between the 1 0 host and the X9421; either between the host and one of the Data Registers or directly between the host and the WCR. These instructions are: – Read Wiper Counter Register—read the current wiper position of the pot, – ...
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... X9421 Figure 5. Three-Byte Instruction Sequence (Write) CS SCL Figure 6. Three-Byte Instruction Sequence (Read) CS SCL Figure 7. Increment/Decrement Instruction Sequence CS SCK Figure 8. Increment/Decrement Timing Limits SCK INC/DEC CMD Issued REV 1.1.6 8/1/ ...
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... X9421 Table 3. Instruction Set Instruction Read Wiper Counter 1 0 Register Write Wiper Counter 1 0 Register Read Data Register 1 0 Write Data Register 1 1 XFR Data Register to Wiper Counter 1 1 Register XFR Wiper Counter Register to Data 1 1 Register Increment/Decrement Wiper Counter ...
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... X9421 on SO instruction opcode (sent by Host on SI instruction register opcode addresses (sent by X9421 on SO instruction register Data Byte opcode addresses (sent by host on SI) ...
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... Rising R R Edge instruction increment/decrement opcode (sent by master on SDA I/D I/D . instruction opcode (sent by X9421 on SO www.xicor.com HIGH-VOLTAGE WRITE CYCLE CS Rising Edge . . . I/D I/D Data Byte CS Rising W Edge ...
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... X9421-2.7 Limits Min. Typ. 150 400 , -120 1.6 300 TOTAL 10/10/25 0.1 www.xicor.com Supply Voltage (V X9421 5V 10% 2.7V to 5.5V Max. Units Test Conditions ± 25°C, each pot ±3 mA 250 Wiper Current = 1000 Wiper Current = ...
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... X9421 D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.) Symbol Parameter I V Supply Current CC1 CC (Active Supply Current CC2 CC (Non-volatile Write Current (Standby Input Leakage Current LI I Output Leakage Current LO V Input HIGH Voltage IH V Input LOW Voltage ...
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... X9421 EQUIVALENT A.C. LOAD CIRCUIT 5V 1533 SDA Output 100pF AC TIMING Symbol f SSI/SPI Clock Frequency SCK t SSI/SPI Clock Cycle Time CYC t SSI/SPI Clock High Time WH t SSI/SPI Clock Low Time WL t Lead Time LEAD t Lag Time LAG t SI, SCK, HOLD and CS Input Setup Time ...
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... X9421 HIGH-VOLTAGE WRITE CYCLE TIMING Symbol t High-voltage Write Cycle Time (Store Instructions) WR XDCP TIMING Symbol t Wiper Response Time After The Third (Last) Power Supply Is Stable WRPO t Wiper Response Time After Instruction Issued (All Load Instructions) WRL Wiper Response Time From An Active SCL/SCK Edge (Increment/Decrement ...
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... X9421 TIMING DIAGRAMS Input Timing CS t LEAD SCK MSB SI High Impedance SO Output Timing CS SCK t MSB SO ADDR SI Hold Timing CS SCK HOLD REV 1.1.6 8/1/02 t CYC ... ... HSU HOLD www.xicor.com LSB ... ...
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... X9421 XDCP Timing (for All Load Instructions) CS SCK MSB High Impedance SO XDCP Timing (for Increment/Decrement Instruction) CS SCK ADDR High Impedance SO Write Protect and Device Address Pins Timing REV 1.1.6 8/1/02 ... ... ... t WRID ... ... Inc/Dec Inc/Dec (Any Instruction WPASU www.xicor.com t WRL ...
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... X9421 APPLICATIONS INFORMATION Electronic potentiometers provide three powerful application advantages: (1) the variability and reliability of a solid- state potentiometer, (2) the flexibility of computer-based digital controls, and (3) the retentivity of nonvolatile memory used for the storage of multiple potentiometer settings or data. Basic Configurations of Electronic Potentiometers ...
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... X9421 PACKAGING INFORMATION 16-Lead Plastic SOIC (300 Mil Body) Package Type S PIN 1 INDEX PIN 1 (4X) 7° 0.050 (1.27) 0.010 (0.25) 0.020 (0.50) 0 – 8 0.015 (0.40) 0.050 (1.27) NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) REV 1.1.6 8/1/02 0.014 (0.35) 0.020 (0.51) 0.403 (10.2 ) 0.413 ( 10. 0.0075 (0.19) 0.420" 0.010 (0.25) FOOTPRINT www.xicor.com 0.290 (7.37) 0.393 (10.00) ...
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... X9421 PACKAGING INFORMATION 0° - 8° See Detail “A” NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) REV 1.1.6 8/1/02 14-Lead Plastic, TSSOP, Package Type V .025 (.65) BSC .169 (4.3) .177 (4.5) .193 (4.9) .200 (5.1) .0075 (.19) .002 (.05) .0118 (.30) .006 (.15) .010 (.25) .019 (.50) .029 (.75) Detail A (20X) www.xicor.com .252 (6.4) BSC .047 (1.20) Gage Plane Seating Plane ...
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... X9421 ORDERING INFORMATION X9421 Device LIMITED WARRANTY Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc. makes no warranty, express, statutory, implied description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. ...