ADS1204

SBAS301A − OCTOBER 2003 − REVISED JUNE 2004

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3

ELECTRICAL CHARACTERISTICS

Over recommended operating free-air temperature range at −40

°C to +85°C, AVDD = 5V, BVDD = 3V, CH x+ = 0.5V to 4.5V, CH x− = 2.5V,

REFIN = REFOUT = internal +2.5V, CLKIN = 20MHz, and 16-bit Sinc3 filter with decimation by 256, unless otherwise noted.

ADS1204I

PARAMETER

TEST CONDITIONS

MIN

TYP(1)

MAX

UNITS

Resolution

16

Bits

DC Accuracy

INL

Integral linearity error(2)

±1

±3

LSB

INL

Integral linearity error(2)

±0.001

±0.005

% FSR

Integral linearity match

6

LSB

Integral linearity match

0.009

% FSR

DNL

Differential nonlinearity(3)

±1

LSB

VOS

Input offset error

−1.4

±3

mV

Input offset error match

2

mV

TCVOS

Input offset error drift

2

8

µV/°C

GERR

Gain error(4)

Referenced to VREF

0.08

±0.5

% FSR

Gain error match

0.185

0.5

% FSR

TCGERR

Gain error drift

2

ppm/

°C

PSRR

Power-supply rejection ratio

4.75V < AVDD < 5.25V

78

dB

Analog Input

FSR

Full-scale differential range

(CH x+) − (CH x−); CH x− = 2.5V

±2.5

V

Specified differential range

(CH x+) − (CH x−); CH x− = 2.5V

±2

V

Maximum operating input range(3)

0

AVDD

V

Input capacitance

Common-mode

3

pF

Input leakage current

CLK turned off

±1

nA

Differential input resistance

100

k

Ω

Differential input capacitance

2.5

pF

CMRR

Common-mode rejection ratio

At DC

100

dB

CMRR

Common-mode rejection ratio

VIN = ±1.25VPP at 40kHz

110

dB

BW

Bandwidth

FS sine wave, −3dB

50

MHz

Sampling Dynamics

Internal clock frequency

CLKSEL = 1

8

10

12

MHz

CLKIN

External clock frequency

CLKSEL = 0

1

20

24

MHz

AC Accuracy

THD

Total harmonic distortion

VIN = ±2VPP at 5kHz

−96

−88

dB

SFDR

Spurious-free dynamic range

VIN = ±2VPP at 5kHz

92

100

dB

SNR

Signal-to-noise ratio

VIN = ±2VPP at 5kHz

86

89

dB

SINAD

Signal-to-noise + distortion

VIN = ±2VPP at 5kHz

85

89

dB

Channel-to-channel isolation(3)

VIN = ±2VPP at 50kHz

85

dB

ENOB

Effective number of bits

14

14.5

Bits

(1) All typical values are at TA = +25°C.

(2) Integral nonlinearity is defined as the maximum deviation of the line through the end points of the specified input range of the transfer curve

for CH x+ = −2V to +2V at 2.5V, expressed either as the number of LSBs or as a percent of measured input range (4V).

(3) Ensured by design.

(4) Maximum values, including temperature drift, are ensured over the full specified temperature range.

(5) Applicable for 5.0V nominal supply: BVDD (min) = 4.5V and BVDD (max) = 5.5V.

(6) Applicable for 3.0V nominal supply: BVDD (min) = 2.7V and BVDD (max) = 3.6V.