AD7781 Analog Devices, AD7781 Datasheet - Page 3

• Manufacturer Part Number: AD7781
• Description: 20-Bit, Pin-Programmable, Ultralow Power Sigma-Delta ADC
• Manufacturer: Analog Devices

Specifications of AD7781

• Resolution (bits): 20bit
• # Chan: 1
• Sample Rate: 16.7SPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Bip
• Ain Range: ± (Vref/Gain) ,10V p-p,78 mV p-p
• Adc Architecture: Sigma-Delta
• Pkg Type: SOIC,SOP

SPECIFICATIONS
AV
Table 2.
Parameter
ADC CHANNEL
ANALOG INPUTS
REFERENCE
BRIDGE POWER-DOWN SWITCH
Output Update Rate (f
No Missing Codes
Resolution, Peak-to-Peak
RMS Noise
Integral Nonlinearity
Offset Error
Offset Error Drift vs. Temperature
Full-Scale Error
Gain Drift vs. Temperature
Power Supply Rejection
Normal Mode Rejection
Common-Mode Rejection
Differential Input Voltage Range
Absolute AIN Voltage Limits
Average Input Current
Average Input Current Drift
External REFIN Voltage
Reference Voltage Range
Absolute REFIN Voltage Limits
Average Reference Input Current
Average Reference Input Current
Normal Mode Rejection
Common-Mode Rejection
(BPDSW)
R
Allowable Current
DD
ON
Drift
50 Hz, 60 Hz
DC
50 Hz, 60 Hz
= 2.7 V to 5.25 V, V
2
2
ADC
REF
2
)
2
= AV
2
2
DD
, DV
Min
20
63
72
GND + 100 mV
GND + 450 mV
GND + 1.1
GND + 1.5
0.5
GND − 30 mV
DD
= 2.7 V to 5.25 V, GND = 0 V, all specifications T
Typ
10
16.7
±6
±6
±200
±1
±10
±10
±150
±10
±0.25
±2
100
120
75
90
90
90
110
±V
±1
±250
±3
AV
400
±0.15
110
REF
DD
Rev. 0 | Page 3 of 16
/gain
Max
AV
AV
AV
AV
AV
AV
9
30
DD
DD
DD
DD
DD
DD
− 100 mV
− 1.1
− 1.1
− 1.5
+ 30 mV
Unit
Hz
Hz
Bits
ppm FSR
μV
μV
μV
μV
nV/°C
nV/°C
nV/°C
% of FS
ppm/°C
dB
dB
dB
dB
dB
dB
dB
V
V
V
V
V
nA
pA
pA/°C
V
V
V
nA/V
nA/V/°C
dB
Ω
mA
MIN
to T
MAX
Test Conditions/Comments
FILTER = 1, settling time = 3/f
FILTER = 0, settling time = 2/f
See Table 7 and Table 8
See Table 7 and Table 8
Gain = 128 with FILTER = 1
Gain = 1 with FILTER = 1
Gain = 128 with FILTER = 0
Gain = 1 with FILTER = 0
Gain = 128
Gain = 1 with FILTER = 1
Gain = 1 with FILTER = 0
Gain = 128, FILTER = 1, AIN = 7.81 mV
Gain = 128, FILTER = 0, AIN = 7.81 mV
50 Hz ± 1 Hz, 60 Hz ± 1 Hz, f
50 Hz ± 1 Hz, 60 Hz ± 1 Hz, f
Gain = 1, AIN = 1 V
Gain = 128, AIN = 7.81 mV
50 Hz ± 1 Hz, 60 Hz ± 1 Hz
V
gain = 1 or 128
Gain = 1
Gain = 128, FILTER = 0
Gain = 128, FILTER = 1, AV
Gain = 128, FILTER = 1, AV
Gain = 1
Gain = 128
REFIN = REFIN(+) − REFIN(−)
Same as for analog inputs
Controlled via the PDRST pin
Continuous current
REF
, unless otherwise noted.
= REFIN(+) − REFIN(−),
DD
DD
AD7781
ADC
ADC
≤ 3.6 V
> 3.6 V
1
ADC
ADC
= 16.7 Hz
= 10 Hz