Texas Instruments ADS868 Series, Manual

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ADS8684, ADS8688
www.ti.com SBAS582C – JULY 2014 – REVISED APRIL 2015
7.5 Electrical Characteristics
Minimum and maximum specifications are at T
A
= –40°C to 125°C. Typical specifications are at T
A
= 25°C.
AVDD = 5 V, DVDD = 3 V, V
REF
= 4.096 V (internal), and f
SAMPLE
= 500 kSPS, unless otherwise noted.
TEST
(1)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
LEVEL
ANALOG INPUTS
Input range = ±2.5 × V
REF
–2.5 × V
REF
2.5 × V
REF
V A
Input range = ±1.25 × V
REF
–1.25 × V
REF
1.25 × V
REF
V A
Full-scale input span
(2)
Input range = ±0.625 × V
REF
–0.625 × V
REF
0.625 × V
REF
V A
(AIN_ n P to AIN_ n GND)
Input range = 2.5 × V
REF
0 2.5 × V
REF
V A
Input range = 1.25 × V
REF
0 1.25 × V
REF
V A
Input range = ±2.5 × V
REF
–2.5 × V
REF
2.5 × V
REF
V A
Input range = ±1.25 × V
REF
–1.25 × V
REF
1.25 × V
REF
V A
Operating input range,
AIN_ n P Input range = ±0.625 × V
REF
–0.625 × V
REF
0.625 × V
REF
V A
positive input
Input range = 2.5 × V
REF
0 2.5 × V
REF
V A
Input range = 1.25 × V
REF
0 1.25 × V
REF
V A
Operating input range,
AIN_ n GND All input ranges –0.1 0 0.1 V B
negative input
At T
A
= 25°C
z
i
Input impedance 0.85 1 1.15 M
Ω
B
All input ranges
Input impedance drift All input ranges 7 25 ppm/°C B
V
IN
– 2.25
With voltage at AIN_ n P pin = V
IN
,
———— µA A
input range = ±2.5 × V
REF
R
IN
V
IN
– 2.00
With voltage at AIN_ n P pin = V
IN
,
———— µA A
input range = ±1.25 × V
REF
R
IN
V
IN
– 1.60
With voltage at AIN_ n P pin = V
IN
,
I
Ikg(in)
Input leakage current ———— µA A
input range = ±0.625 × V
REF
R
IN
V
IN
– 2.50
With voltage at AIN_ n P pin = V
IN
,
———— µA A
input range = 2.5 × V
REF
R
IN
V
IN
– 2.50
With voltage at AIN_ n P pin = V
IN
,
———— µA A
input range = 1.25 × V
REF
R
IN
INPUT OVERVOLTAGE PROTECTION
AVDD = 5 V or offers low
–20 20 V B
impedance < 30 k Ω , all input ranges
V
OVP
Overvoltage protection voltage
AVDD = floating with impedance
–11 11 V B
> 30 k Ω , all input ranges
(1) Test Levels: (A) Tested at final test. Over temperature limits are set by characterization and simulation. (B) Limits set by characterization
and simulation, across temperature range. (C) Typical value only for information, provided by design simulation.
(2) Ideal input span, does not include gain or offset error.
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