Datasheet

ADS1194, ADS1196
ADS1198
www.ti.com SBAS471C –APRIL 2010– REVISED NOVEMBER 2011
ELECTRICAL CHARACTERISTICS
Minimum/maximum specifications apply from 0°C to +70°C. Typical specifications are at +25°C.
All specifications at DVDD = 1.8V, AVDD – AVSS = 3V, V
REF
= 2.4V, external f
CLK
= 2.048MHz, data rate = 500SPS, and
gain = 6, unless otherwise noted.
ADS1194, ADS1196, ADS1198
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
ANALOG INPUTS
Full-scale differential input voltage
±V
REF
/GAIN V
(AINP – AINN)
See the Input Common-Mode Range
Input common-mode range subsection of the PGA Settings and Input
Range section
Input capacitance 20 pF
Input = 1.5V, T
A
= +25°C ±200 pA
Input bias current
Input = 1.5V T
A
= 0°C to +70°C ±1 nA
No lead-off 1000 MΩ
DC input impedance Current source lead-off detection 500 MΩ
Pull-up resistor lead-off detection 10 MΩ
PGA PERFORMANCE
Gain settings 1, 2, 3, 4, 6, 8, 12
Bandwidth See Table 4
ADC PERFORMANCE
Resolution No missing codes 16 Bits
Data rate 125 8000 SPS
CHANNEL PERFORMANCE
DC Performance
Gain = 6
(1)
, 10 seconds of data 12.2 µV
PP
Gain = 6, 256 points, 0.5 seconds of
Input-referred noise 12.6 µV
PP
data
Gain settings other than 6 See Noise Measurements section
Integral nonlinearity Full-scale with gain = 6, best fit ±1 LSB
(2)
Offset error ±500 μV
Offset error drift 2 μV/°C
Gain error Excluding voltage reference error ±0.2 ±0.5 % of FS
Gain drift Excluding voltage reference drift 5 ppm/°C
Gain match between channels 0.3 % of FS
AC Performance
Common-mode rejection ratio (CMRR) f
CM
= 50Hz, 60Hz
(3)
–100 –105 dB
Power-supply rejection ratio (PSRR) f
PS
= 50Hz, 60Hz 85 dB
Crosstalk f
IN
= 50Hz, 60Hz –100 dB
Signal-to-noise ratio (SNR) f
IN
= 10Hz input, gain = 6 97 dB
Total harmonic distortion (THD) 10Hz, –0.5dBFs –95 dB
DIGITAL FILTER
–3dB bandwidth 0.262f
DR
Hz
Digital filter settling Full setting 4 Conversions
(1) Noise data measured in a 10-second interval. Test not performed in production. Input-referred noise is calculated with input shorted
(without electrode resistance) over a 10-second interval.
(2) Input referred LSB in volts = (2 × V
REF
/(Gain*2
16
)).
(3) CMRR is measured with a common-mode signal of AVSS + 0.3V to AVDD – 0.3V. The values indicated are the minimum of the eight
channels.
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Product Folder Link(s): ADS1194 ADS1196 ADS1198