Datasheet

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SBAS314B − APRIL 2004 − REVISED JANUARY 2009
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3
ELECTRICAL CHARACTERISTICS
All specifications at T
A
= −40°C to +85°C, VDD = +5V, f
CLK
= 2MHz, and V
REF
= +2.5V, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Analog Input
Full-scale input voltage AINP − AINN ±2V
REF
V
Absolute input voltage
Buffer off; AINP, AINN with respect to GND GND − 0.1 VDD + 0.1 V
Absolute input voltage
Buffer on; AINP, AINN with respect to GND GND + 0.05 VDD − 1.5 V
Differential input impedance
Buffer off; f
CLK
= 2MHz 2.7 MΩ
Differential input impedance
Buffer on; f
CLK
= 2MHz 1.2 GΩ
Common-mode input impedance Buffer off; f
CLK
= 2MHz 5.4 MΩ
System Performance
Resolution No missing codes 24 Bits
Data rate 120 (f
CLK
/2MHz) SPS
(1)
Integral nonlinearity (INL)
Buffer off; Differential input signal, end point fit 0.0003 0.0015 % of FSR
(2)
Integral nonlinearity (INL)
Buffer on; Differential input signal, end point fit 0.0006 % of FSR
Offset error
Buffer off 50 150 µV
Offset error
Buffer on 50 µV
Offset error drift
Buffer off 0.2 µV/°C
Offset error drift
Buffer on 0.2 µV/°C
Offset error match Between channels 20 100 µV
Gain error
Buffer off 0.004 0.025 %
Gain error
Buffer on 0.008 %
Gain error drift
Buffer off 0.00003 % of FSR/°C
Gain error drift
Buffer on 0.00006 % of FSR/°C
Gain error match Between channels 0.0005 %
Common-mode rejection
Buffer off; at DC 95 dB
Common-mode rejection
Buffer on; at DC 90 100 dB
Power-supply rejection
Buffer off; at DC, VDD = 2.7V to 5.5V 90 dB
Power-supply rejection
Buffer on; at DC, VDD = 2.7V to 5.5V 90 dB
Noise 0.8 ppm of FSR, rms
Temperature Sensor
Temperature sensor voltage T
A
= 25°C 106 mV
Temperature sensor coefficient 360 µV/°C
Voltage Reference Input
Reference input voltage V
REF
= VREFP − VREFN 0.5 2.5 VDD
(3)
V
Negative reference input Buffer off GND − 0.1 VREFP − 0.5 V
Positive reference input Buffer off VREFN + 0.5 VDD + 0.1 V
Negative reference input Buffer on GND + 0.05 VREFP − 0.5 V
Positive reference input Buffer on VREFN + 0.5 VDD − 1.5 V
Voltage reference impedance f
CLK
= 2MHz 500 kΩ
(1)
SPS = samples per second.
(2)
FSR = full-scale range = 4V
REF
.
(3)
It will not be possible to reach the digital output full-scale code when V
REF
> VDD/2.