AD1938Data SheetPin No.In/Out MnemonicDescription 26 I CCLK Control Clock Input (SPI). 27 I CLATCH Latch Input for Control Data (SPI). 28 O OL1 DAC 1 Left Output. 29 O OR1 DAC 1 Right Output. 30 O OL2 DAC 2 Left Output. 31 O OR2 DAC 2 Right Output. 32 I AGND Analog Ground. 33 I AVDD Analog Power Supply. Connect to analog 3.3 V supply. 34 I AGND Analog Ground. 35 O FILTR Voltage Reference Filter Capacitor Connection. Bypass with 10 µF||100 nF to AGND. 36 I AGND Analog Ground. 37 I AVDD Analog Power Supply. Connect to analog 3.3 V supply. 38 O CM Common-Mode Reference Filter Capacitor Connection. Bypass with 47 µF||100 nF to AGND. 39 I ADC1LP ADC1 Left Positive Input. 40 I ADC1LN ADC1 Left Negative Input. 41 I ADC1RP ADC1 Right Positive Input. 42 I ADC1RN ADC1 Right Negative Input. 43 I ADC2LP ADC2 Left Positive Input. 44 I ADC2LN ADC2 Left Negative Input. 45 I ADC2RP ADC2 Right Positive Input. 46 I ADC2RN ADC2 Right Negative Input. 47 O LF PLL Loop Filter, Return to AVDD. 48 I AVDD Analog Power Supply. Connect to analog 3.3 V supply. Rev. E | Page 10 of 32 Document Outline Features Applications General Description Functional Block Diagram Revision History Specifications Test Conditions Analog Performance Specifications Crystal Oscillator Specifications Digital Input/Output Specifications Power Supply Specifications Digital Filters Timing Specifications Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Analog-to-Digital Converters (ADCs) Digital-to-Analog Converters (DACs) Clock Signals Reset and Power-Down Serial Control Port Power Supply and Voltage Reference Serial Data Ports—Data Format Time-Division Multiplexed (TDM) Modes Daisy-Chain Mode Control Registers Definitions PLL and Clock Control Registers DAC Control Registers ADC Control Registers Additional Modes Applications Circuits Outline Dimensions Ordering Guide Automotive Products