ADS7844

2

SBAS100A

www.ti.com

SPECIFICATION: +5V

At TA = –40°C to +85°C, +VCC = +5V, VREF = +5V, fSAMPLE = 200kHz, and fCLK = 16 • fSAMPLE = 3.2MHz, unless otherwise noted.

ADS7844E, N

ADS7844EB, NB

PARAMETER

CONDITIONS

MIN

TYP

MAX

MIN

TYP

MAX

UNITS

ANALOG INPUT

Full-Scale Input Span

Positive Input - Negative Input

0

VREF

✻✻

V

Absolute Input Range

Positive Input

–0.2

+VCC +0.2

✻✻

V

Negative Input

–0.2

+1.25

✻✻

V

Capacitance

25

✻

pF

Leakage Current

±1

✻

µA

SYSTEM PERFORMANCE

Resolution

12

✻

Bits

No Missing Codes

12

✻

Bits

Integral Linearity Error

±2

±1

LSB(1)

Differential Linearity Error

±0.8

±0.5

±1

LSB

Offset Error

±3

✻

LSB

Offset Error Match

0.15

1.0

✻✻

LSB

Gain Error

±4

±3

LSB

Gain Error Match

0.1

1.0

✻✻

LSB

Noise

30

✻

µVrms

Power Supply Rejection

70

✻

dB

SAMPLING DYNAMICS

Conversion Time

12

✻

Clk Cycles

Acquisition Time

3

✻

Clk Cycles

Throughput Rate

200

✻

kHz

Multiplexer Settling Time

500

✻

ns

Aperture Delay

30

✻

ns

Aperture Jitter

100

✻

ps

DYNAMIC CHARACTERISTICS

Total Harmonic Distortion(2)

VIN = 5VPP at 10kHz

–76

–78

dB

Signal-to-(Noise + Distortion)

VIN = 5VPP at 10kHz

71

72

dB

Spurious Free Dynamic Range

VIN = 5VPP at 10kHz

76

78

dB

Channel-to-Channel Isolation

VIN = 5VPP at 50kHz

120

✻

dB

REFERENCE INPUT

Range

0.1

+VCC

✻✻

V

Resistance

DCLK Static

5

✻

G

Ω

Input Current

45

100

✻✻

µA

fSAMPLE = 12.5kHz

2.5

✻

µA

DCLK Static

0.001

3

✻✻

µA

DIGITAL INPUT/OUTPUT

Logic Family

CMOS

✻

Logic Levels

VIH

| IIH | ≤ +5µA

3.0

5.5

✻✻

V

VIL

| IIL | ≤ +5µA

–0.3

+0.8

✻✻

V

VOH

IOH = –250µA

3.5

✻

V

VOL

IOL = 250µA

0.4

✻

V

Data Format

Straight Binary

✻

POWER SUPPLY REQUIREMENTS

+VCC

Specified Performance

4.75

5.25

✻✻

V

Quiescent Current

550

900

✻

µA

fSAMPLE = 12.5kHz

300

✻

µA

Power-Down Mode(3), CS = +VCC

3

✻

µA

Power Dissipation

4.5

✻

mW

TEMPERATURE RANGE

Specified Performance

–40

+85

✻✻

°C

✻ Same specifications as ADS7844E, ADS7844N.

NOTE: (1) LSB means Least Significant Bit. With VREF equal to +5.0V, one LSB is 1.22mV. (2) First five harmonics of the test frequency. (3) Auto power-down mode

(PD1 = PD0 = 0) active or SHDN = GND.