Datasheet

–2–
AD7783–SPECIFICATIONS
1
(V
DD
= 2.7 V to 3.6 V or 4.75 V to 5.25 V, REFIN(+) = 2.5 V; REFIN(–) = GND;
GND = 0 V; XTAL1/XTAL2 = 32.768 kHz Crystal; all specifications T
MIN
to T
MAX
, unless otherwise noted.)
Parameter AD7783B Unit Test Conditions
ADC CHANNEL SPECIFICATION
Output Update Rate 19.79 Hz nom
ADC CHANNEL
No Missing Codes
2
24 Bits min
Resolution 16 Bits p-p ± 160 mV Range, RANGE = 0
18 Bits p-p ± 2.56 V Range, RANGE = 1
Output Noise See Table I
Integral Nonlinearity ± 10 ppm of FSR max Typically 2 ppm,
Offset Error ± 3 mV typ AIN(+) = AIN(–) = 2.5 V
Offset Error Drift versus Temperature ± 10 nV/∞C typ
Full-Scale Error ± 10 mV typ V
DD
= 3 V
Gain Drift versus Temperature ± 0.5 ppm/∞C typ
Power Supply Rejection (PSR) 100 dB typ Input Range = ± 160 mV, V
IN
= 1/16 V
85 dB typ Input Range = ± 2.56 V, V
IN
= 1 V
ANALOG INPUTS
Differential Input Voltage Ranges ± 160 mV nom Range = 0
± 2.56 V nom Range = 1
ADC Range Matching ± 2 mV typ Input Voltage = 159 mV on Both Ranges
Absolute AIN Voltage Limits GND + 100 mV V min
V
DD
– 100 mV V max
Analog Input Current
2
DC Input Current ± 1nA max
DC Input Current Drift ± 5pA/∞C typ
Normal-Mode Rejection
2, 3
@ 50 Hz 60 dB min 50 Hz ± 1 Hz
@ 60 Hz 94 dB min 60 Hz ± 1 Hz
Common-Mode Rejection Input Range = ± 160 mV, V
IN
= 1/16 V
@ DC 105 dB min 125 dB typ,
110 dB typ when Input Range = ± 2.56 V
@ 50 Hz
2
100 dB min 50 Hz ± 1 Hz
@ 60 Hz
2
100 dB min 60 Hz ± 1 Hz
REFERENCE INPUT
REFIN Voltage 2.5 V nom REFIN = REFIN(+) – REFIN(–)
REFIN Voltage Range
2
1V min
V
DD
V max
Absolute REFIN Voltage Limits
2
GND – 30 mV V min
V
DD
+ 30 mV V max
Average Reference Input Current 0.5 mA/V typ
Average Reference Input Current Drift ± 0.01 nA/V/∞C typ
Normal-Mode Rejection
2, 3
@ 50 Hz 60 dB min 50 Hz ± 1 Hz
@ 60 Hz 94 dB min 60 Hz ± 1 Hz
Common-Mode Rejection Input Range = ± 160 mV, V
IN
= 1/16 V
@ DC 100 dB typ
@ 50 Hz 110 dB typ 50 Hz ± 1 Hz
@ 60 Hz 110 dB typ 60 Hz ± 1 Hz
EXCITATION CURRENT SOURCES
(IEXC1, IEXC2)
Output Current 200 mA
Initial Tolerance at 25∞C ± 10 % typ
Drift 200 ppm/∞C typ
Initial Current Matching at 25∞C ± 2.5 % max No Load
Drift Matching 20 ppm/∞C typ
Line Regulation 2.5 mA/V max V
DD
= 5 V ± 5%. Typically 1.25 mA/V.
Load Regulation 300 nA/V typ
Output Compliance V
DD
– 0.6 V max
GND – 30 mV V min
FSR
REFIN
Gain
=
¥21024.
REV. C