link to page 16 AD5232Data SheetPIN CONFIGURATION AND FUNCTION DESCRIPTIONSCLK 116RDYSDI215CSSDO314PRAD5232GND4TOP VIEW13WP(Not to Scale)V5SS12VDDA1611A2W1710W2B189B2 004 02618- Figure 4. Pin Configuration Table 5. Pin Function Descriptions Pin No.Mnemonic Description 1 CLK Serial Input Register Clock. Shifts in one bit at a time on positive clock edges. 2 SDI Serial Data Input. The MSB is loaded first. 3 SDO Serial Data Output. This open-drain output requires an external pull-up resistor. Command Instruction 9 and Command Instruction 10 activate the SDO output (see Table 8). Other commands shift out the previously loaded SDI bit pattern delayed by 16 clock pulses, allowing daisy-chain operation of multiple packages. 4 GND Ground, Logic Ground Reference. 5 VSS Negative Power Supply. Connect to 0 V for single-supply applications. 6 A1 Terminal A of RDAC1. 7 W1 Wiper Terminal W of RDAC1, ADDR (RDAC1) = 0x0. 8 B1 Terminal B of RDAC1. 9 B2 Terminal B of RDAC2. 10 W2 Wiper Terminal W of RDAC2, ADDR (RDAC2) = 0x1. 11 A2 Terminal A of RDAC2. 12 VDD Positive Power Supply. 13 WP Write Protect. When active low, WP prevents any changes to the present register contents, except PR, Command Instruction 1, and Command Instruction 8, which refresh the RDACx register from EEMEM. Execute an NOP instruction (Command Instruction 0) before returning WP to logic high. 14 PR Hardware Override Preset. Refreshes the scratch pad register with current contents of the EEMEMx register. Factory default loads Midscale 0x80 until EEMEMx is loaded with a new value by the user (PR is activated at the logic high transition). 15 CS Serial Register Chip Select, Active Low. Serial register operation takes place when CS returns to logic high. 16 RDY Ready. This active-high, open-drain output requires a pull-up resistor. Identifies completion of Command Instruction 2, Command Instruction 3, Command Instruction 8, Command Instruction 9, Command Instruction 10, and PR. Rev. C | Page 8 of 24 Document Outline Features Applications Functional Block Diagram General Description Revision History Specifications Electrical Characteristics—10 kΩ, 50 kΩ, 100 kΩ Versions Interface Timing Characteristics Timing Diagrams Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Test Circuits Theory of Operation Scratch Pad and EEMEM Programming Basic Operation EEMEM Protection Digital Input/Output Configuration Serial Data Interface Daisy-Chaining Operation Advanced Control Modes Increment and Decrement Commands Logarithmic Taper Mode Adjustment Using Additional Internal, Nonvolatile EEMEM Terminal Voltage Operating Range Detailed Potentiometer Operation Programming the Variable Resistor Rheostat Operation Programming the Potentiometer Divider Voltage Output Operation Operation from Dual Supplies Application Programming Examples Equipment Customer Start-up Sequence for a PCB Calibrated Unit with Protected Settings Flash/EEMEM Reliability Evaluation Board Outline Dimensions Ordering Guide