AD7738CStt4t86SCLKt7t5tt95ADOUTMSBLSB Figure 1. Read Cycle Timing Diagram CStt1116t14SCLKtt1512t13DINMSBLSB Figure 2. Write Cycle Timing Diagram ISINK (800A AT DVDD = 5V 100A AT DVDD = 3V)TOOUTPUT1.6VPIN50pFISOURCE ( 200A AT DVDD = 5V 100A AT DVDD = 3V) Figure 3. Load Circuit for Access Time and Bus Relinquish Time REV. 0 –5– Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ORDERING GUIDE PIN CONFIGURATION PIN FUNCTION DESCRIPTION PIN FUNCTION DESCRIPTION (continued) OUTPUT NOISE AND RESOLUTION SPECIFICATION CHOPPING ENABLED CHOPPING DISABLED Typical Performance Characteristics REGISTER DESCRIPTION Communications Register I/O Port Register Revision Register Test Register ADC Status Register Checksum Register ADC Zero Scale Calibration Register ADC Full-Scale Register Channel Data Registers Channel Zero-Scale Calibration Registers Channel Full-Scale Calibration Registers Channel Status Registers Channel Setup Registers Channel Conversion Time Registers Mode Register DIGITAL INTERFACE DESCRIPTION Hardware Reset Access the AD7738 Registers Single Conversion and Reading Data Dump Mode Continuous Conversion Mode Continuous Read (Continuous Conversion) Mode CIRCUIT DESCRIPTION Analog Front End Sigma-Delta ADC Chopping Multiplexer, Conversion, and Data Output Timing Frequency Response Analog Inputs Voltage Range Analog Inputs Extended Voltage Range Voltage Reference Inputs Reference Detect I/O Port CALIBRATION ADC Zero-Scale Self-Calibration Per Channel System Calibration OUTLINE DIMENSIONS