Datasheet AD7790 (Analog Devices) - 4

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Data Sheet AD7790 AD7790—SPECIFICATIONS1 Table 1. (VDD = 2.5 V to 5.25 V; REFIN(+) = 2.5 V; REFIN(–) = GND; CDIV1 = CDIV0 = 0; GND = 0 V; all specifications TMIN to TMAX, unless otherwise noted.) Parameter AD7790B Unit Test Conditions/Comments
ADC CHANNEL SPECIFICATION Output Update Rate 9.5 Hz min nom 120 Hz max nom ADC CHANNEL No Missing Codes2 16 Bits min ±VREF Range, Update Rate ≤ 20 Hz Resolution 16 Bits p-p 9.5 Hz Update Rate Output Noise 1.1 µV rms typ Integral Nonlinearity ±15 ppm of FSR max 3.5 ppm typ 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 Input Range = ±REFIN, 100 dB typ ANALOG INPUTS Differential Input Voltage Ranges ±REFIN/GAIN V nom REFIN = REFIN(+) – REFIN(–); GAIN = 1, 2, 4, or 8 Absolute AIN Voltage Limits2 GND + 100 mV V min Buffered Mode of Operation VDD – 100 mV V max Analog Input Current Buffered Mode of Operation Average Input Current2 ±1 nA max Average Input Current Drift ±5 pA/°C typ Absolute AIN Voltage Limits2 GND – 30 mV V min Unbuffered Mode of Operation VDD + 30 mV V max Analog Input Current Unbuffered Mode of Operation Input current varies with input voltage. Average Input Current ±400 nA/V typ Average Input Current Drift ±50 pA/V/°C typ Normal Mode Rejection2 @ 50 Hz, 60 Hz 65 dB min 73 dB typ, 50 ± 1 Hz, 60 ± 1 Hz, FS[2:0] = 1004 @ 50 Hz 80 dB min 90 dB typ, 50 ± 1 Hz, FS[2:0] = 1014 @ 60 Hz 80 dB min 90 dB typ, 60 ± 1 Hz, FS[2:0] = 0114 Common Mode Rejection Input Range = ±REFIN, AIN = 1 V @ DC 90 dB min 100 dB typ (FS[2:0] = 1004) @ 50 Hz, 60 Hz2 100 dB min 50 ± 1 Hz (FS[2:0] = 1014), 60 ± 1 Hz (FS[2:0] = 0114) REFERENCE INPUT REFIN = REFIN(+) – REFIN(–) REFIN Voltage 2.5 V nom Reference Voltage Range2 0.1 V min V DD 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 1 Temperature Range –40°C to +105°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). 4 FS[2:0] are the three bits used in the filter register to select the output word rate. Rev. A | Page 3 of 20 Document Outline AD7790—Specifications Timing Characteristics 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) Mode Register (RS1, RS0 = 0, 1; Power-on/Reset = 0x02) Filter Register (RS1, RS0 = 1, 0; Power-on/Reset = 0x04) Data Register (RS1, RS0 = 1, 1; Power-on/Reset = 0x0000) ADC Circuit Information Overview Noise Performance Reduced Current Modes Digital Interface Single Conversion Mode Continuous Conversion Mode Continuous Read Mode Circuit Description Analog Input Channel Programmable Gain Amplifier Bipolar Configuration Data Output Coding Reference Input VDD Monitor Grounding and Layout Outline Dimensions Ordering Guide