Datasheet
ADS1231
www.ti.com
SBAS414D –JULY 2009–REVISED OCTOBER 2013
ELECTRICAL CHARACTERISTICS
Minimum/maximum limit specifications apply from –40°C to +85°C. Typical specifications at +25°C.
All specifications at AVDD = DVDD = VREFP = +5V, V
CM
= 2.5V and VREFN = GND, unless otherwise noted.
ADS1231
PARAMETER CONDITIONS MIN TYP MAX UNIT
ANALOG INPUTS
±0.5V
REF
/ 128 V
Full-scale input voltage (AINP – AINN) V
REF
= AVDD = 5V ±19.5 mV
V
REF
= AVDD = 3V ±11.7 mV
Common-mode input range GND + 1.5 AVDD – 1.5 V
Differential input current ±2 nA
LOW-SIDE POWER SWITCH
AVDD = 5V, I
SW
= 30mA 3.5 5 Ω
On-resistance (R
ON
)
AVDD = 3V, I
SW
= 30mA 4 7 Ω
Current through switch 30 mA
SYSTEM PERFORMANCE
Resolution No missing codes 24 Bits
Internal oscillator, SPEED = high 80 SPS
Internal oscillator, SPEED = low 10 SPS
Data rate
External clock, SPEED = high f
CLKIN
/ 61,440 SPS
External clock, SPEED = low f
CLKIN
/ 491,520 SPS
Digital filter settling time Full settling 4 Conversions
f
DATA
= 10SPS, AVDD = V
REF
= 5V 35 nV, rms
f
DATA
= 80SPS, AVDD = V
REF
= 5V 102 nV, rms
Noise
f
DATA
= 10SPS, AVDD = V
REF
= 5V 232 nV, P-P
f
DATA
= 80SPS, AVDD = V
REF
= 5V 622 nV, P-P
Integral nonlinearity (INL) Differential input, end-point fit ±8 ppm
Input offset error 10 μV
Input offset drift ±20 nV/°C
Gain error 1 %
Gain drift ±2 ppm/°C
f
IN
= 50Hz or 60Hz ±1Hz, f
DATA
= 10SPS,
80 100 dB
internal oscillator
Normal-mode rejection
(1)
f
IN
= 50Hz or 60Hz ±1Hz, f
DATA
= 10SPS,
90 110 dB
external clock
(2)
Common-mode rejection At dc 110 dB
Power-supply rejection At dc 90 100 dB
VOLTAGE REFERENCE INPUT
Voltage reference input (V
REF
) V
REF
= VREFP – VREFN 1.5 AVDD AVDD + 0.1 V
Negative reference input (VREFN) GND – 0.1 VREFP – 1.5 V
Positive reference input (VREFP) VREFN + 1.5 AVDD + 0.1 V
Voltage reference input current 10 nA
DIGITAL INPUT/OUTPUT (DVDD = 3V to 5.3V)
V
IH
0.8 DVDD DVDD + 0.1 V
V
IL
GND 0.2 DVDD V
Logic levels
V
OH
I
OH
= 500μA DVDD – 0.4 V
V
OL
I
OL
= 500μA 0.2 DVDD V
Input leakage 0 < V
DIGITAL INPUT
< DVDD ±10 μA
External clock input frequency (f
CLKIN
) 1 4.9152 6 MHz
Serial clock input frequency (f
SCLK
) 5 MHz
(1) Specification is assured by the combination of design and final test.
(2) f
CLKIN
= 4.9152MHz.
Copyright © 2009–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: ADS1231