Datasheet AD7788, AD7789 (Analog Devices) - 4

AD7788/AD7789 Data Sheet AD7788
VDD = 2.5 V to 5.25 V (B grade); VDD = 2.7 V to 5.25 V (A grade); REFIN(+) = 2.5 V; REFIN(−) = GND; GND = 0 V; all specifications TMIN to TMAX, unless otherwise noted.
Table 2. Parameter1 AD7788A, AD7788B Unit Test Conditions/Comments
ADC CHANNEL SPECIFICATION Output Update Rate 16.6 Hz nom ADC CHANNEL No Missing Codes2 16 Bits min Resolution 16 Bits p-p Output Noise 1.5 µV rms typ Integral Nonlinearity ±15 ppm of FSR max B grade ±50 ppm of FSR max A grade2 Offset Error ±3 µV typ Offset Error Drift vs. Temperature ±10 nV/°C typ Full-Scale Error3 ±10 µV typ Gain Drift vs. Temperature ±0.5 ppm/°C typ Power Supply Rejection 90 dB min B grade 90 dB typ A grade ANALOG INPUTS Differential Input Voltage Ranges ±REFIN V nom REFIN = REFIN(+) − REFIN(−) Absolute AIN Voltage Limits2 GND − 30 mV V min VDD + 30 mV V max Analog Input Current Input current varies with input voltage Average Input Current2 ±400 nA/V typ Average Input Current Drift ±50 pA/V/°C typ Normal-Mode Rejection2 At 50 Hz, 60 Hz 65 dB min B grade, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz 60 dB min A grade, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz Common-Mode Rejection AIN = 1 V At DC 90 dB min B grade, 100 dB typ 90 dB typ A grade At 50 Hz, 60 Hz2 100 dB min B grade, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz 100 dB typ A grade, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz REFERENCE INPUT REFIN Voltage 2.5 V nom REFIN = REFIN(+) − REFIN(−) Reference Voltage Range2 0.1 V min VDD V max Absolute REFIN Voltage Limits2 GND − 30 mV V min VDD + 30 mV V max Average Reference Input Current 0.5 µA/V typ Average Reference Input Current Drift ±0.03 nA/V/°C typ Normal-Mode Rejection2 At 50 Hz, 60 Hz 65 dB min B grade, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz 60 dB min A grade Common-Mode Rejection AIN = 1 V At DC 100 dB typ At 50 Hz, 60 Hz 110 dB typ 50 Hz ± 1 Hz, 60 Hz ± 1 Hz 1 Temperature range: B grade: −40°C to +105°C; A grade: −40°C to +85°C. 2 Specification is not production tested but is supported by characterization data at initial product release. 3 Full-scale error applies to both positive and negative full scale and applies at the factory calibration conditions (VDD = 4 V). Rev. C | Page 4 of 20 Document Outline FEATURES INTERFACE APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION TABLE OF CONTENTS SPECIFICATIONS AD7789 AD7788 AD7788/AD7789 TIMING CHARACTERISTICS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS ON-CHIP REGISTERS COMMUNICATIONS REGISTER (RS1, RS0 = 0, 0) STATUS REGISTER (RS1, RS0 = 0, 0; Power-On/Reset = 0x88 for AD7788 and 0x8C for AD7789) MODE REGISTER (RS1, RS0 = 0, 1; Power-On/Reset = 0x02) DATA REGISTER (RS1, RS0 = 1, 1; Power-On/Reset = 0x0000 for the AD7788 and 0x000000 for the AD7789) ADC CIRCUIT INFORMATION NOISE PERFORMANCE DIGITAL INTERFACE Single Conversion Mode Continuous Conversion Mode Continuous Read Mode CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL BIPOLAR/UNIPOLAR CONFIGURATION DATA OUTPUT CODING REFERENCE INPUT VDD MONITOR GROUNDING AND LAYOUT OUTLINE DIMENSIONS ORDERING GUIDE NOTES