Datasheet

AD7191
Rev. A | Page 4 of 20
Parameter
1
AD7191B Unit Test Conditions/Comments
Analog Input Current
Input Current
2
±2 nA max Gain = 1
±3 nA max Gain > 1
Input Current Drift ±5 pA/°C typ
REFERENCE INPUT
REFIN Voltage AV
DD
V nom
REFIN = REFIN(+) − REFIN(−).
Reference Voltage Range
2
1 V min
AV
DD
V max
The differential input must be limited to
±(AV
DD
− 1.25 V)/gain when gain > 1.
Absolute REFIN Voltage Limits
2
AGND – 50 mV V min
AV
DD
+ 50 mV V max
Average Reference Input Current 4.5 μA/V typ
Average Reference Input Current
Drift
±0.03 nA/V/°C typ External clock.
±1.3 nA/V/°C typ Internal clock.
Normal-Mode Rejection
2
Same as for analog
inputs
Common-Mode Rejection 100 dB typ
TEMPERATURE SENSOR
Accuracy +2 °C typ Applies after user calibration at one temperature.
Sensitivity 2815 Codes/°C typ
BRIDGE POWER-DOWN SWITCH
R
ON
10 Ω max
Allowable Current
2
30 mA max Continuous current.
INTERNAL/EXTERNAL CLOCK
Internal Clock
Frequency 4.92 + 4% MHz min/MHz max
Duty Cycle 50:50 % typ
External Clock/Crystal
Frequency 4.9152 MHz nom
2.4576/5.12 MHz min/MHz max
Input Low Voltage, V
INL
0.8 V max DV
DD
= 5 V.
0.4 V max DV
DD
= 3 V.
Input High Voltage, V
INH
2.5 V min DV
DD
= 3 V.
3.5 V min DV
DD
= 5 V.
Input Current ±10 μA max MCLKIN = DV
DD
or DGND.
LOGIC INPUTS
Input High Voltage, V
INH
2
2 V min
Input Low Voltage, V
INL
2
0.8 V max
Hysteresis
2
0.1/0.25 V min/V max
Input Currents ±10 μA max V
IN
= DV
DD
or DGND.
LOGIC OUTPUT (DOUT/RDY)
Output High Voltage, V
OH
2
DV
DD
− 0.6
V min DV
DD
= 3 V, I
SOURCE
= 100 μA.
Output Low Voltage, V
OL
2
0.4 V max DV
DD
= 3 V, I
SINK
= 100 μA.
Output High Voltage, V
OH
2
4 V min DV
DD
= 5 V, I
SOURCE
= 200 μA.
Output Low Voltage, V
OL
2
0.4 V max DV
DD
= 5 V, I
SINK
= 1.6 mA.