Data Sheet
AD7790
Rev. A | Page 3 of 20
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
16
Bits min
±VREF Range, Update Rate
≤ 20 Hz
Resolution
16
Bits p-p
9.5 Hz Update Rate
Output Noise
1.1
V rms typ
Integral Nonlinearity
±15
ppm of FSR max
3.5 ppm typ
Offset Error
±3
V typ
Offset Error Drift vs. Temperature
±10
nV/°C typ
±10
V 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 Limit
s2GND + 100 mV
V min
Buffered Mode of Operation
VDD – 100 mV
V max
Analog Input Current
Buffered Mode of Operation
±1
nA max
Average Input Current Drift
±5
pA/°C typ
Absolute AIN Voltage Limit
s2GND – 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
@ 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] = 1
014@ 60 Hz
80
dB min
90 dB typ, 60 ± 1 Hz, FS[2:0] = 0
114Common Mode Rejection
Input Range = ±REFIN, AIN = 1 V
@ DC
90
dB min
100 dB typ (FS[2:0] =
1004)100
dB min
50 ± 1 Hz (FS[2:0] =
1014), 60 ± 1 Hz (FS[2:0] = 0
114)REFERENCE INPUT
REFIN = REFIN(+) – REFIN(–)
REFIN Voltage
2.5
V nom
0.1
V min
V DD
V max
Absolute REFIN Voltage Limit
s2GND – 30 mV
V min
VDD + 30 mV
V max
Average Reference Input Current
0.5
A/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.