ADS7844

12-Bit, 8-Channel Serial Output Sampling

ANALOG-TO-DIGITAL CONVERTER

FEATURES

q SINGLE SUPPLY: 2.7V to 5V

q 8-CHANNEL SINGLE-ENDED OR

4-CHANNEL DIFFERENTIAL INPUT

q UP TO 200kHz CONVERSION RATE

q

±1 LSB MAX INL AND DNL

q NO MISSING CODES

q 72dB SINAD

q SERIAL INTERFACE

q 20-LEAD QSOP AND

20-LEAD SSOP PACKAGES

q ALTERNATE SOURCE FOR MAX147

DESCRIPTION

The ADS7844 is an 8-channel, 12-bit sampling analog-to-

digital converter (ADC) with a synchronous serial interface.

Typical power dissipation is 3mW at a 200kHz throughput

rate and a +5V supply. The reference voltage (VREF) can be

varied between 100mV and VCC, providing a corresponding

input voltage range of 0V to VREF. The device includes a

shutdown mode that reduces power dissipation to under

1

µW. The ADS7844 is ensured down to 2.7V operation.

Low power, high speed, and onboard multiplexer make the

ADS7844 ideal for battery-operated systems such as personal

digital assistants, portable multichannel data loggers, and

measurement equipment. The serial interface also provides

low-cost isolation for remote data acquisition. The ADS7844

is available in a 20-lead QSOP package and the MAX147

equivalent 20-lead SSOP package and is ensured over the

–40

°C to +85°C temperature range.

APPLICATIONS

q DATA ACQUISITION

q TEST AND MEASUREMENT

q INDUSTRIAL PROCESS CONTROL

q PERSONAL DIGITAL ASSISTANTS

q BATTERY-POWERED SYSTEMS

CDAC

SAR

Comparator

Eight

Channel

Multiplexer

Serial

Interface

and

Control

CH4

CH5

CH6

CH7

COM

V

REF

CH0

CH1

CH2

CH3

CS

SHDN

DIN

DOUT

BUSY

DCLK

ADS7

844

ADS7844

SBAS100A – JANUARY 1998 – REVISED OCTOBER 2003

www.ti.com

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Copyright © 1998-2003, Texas Instruments Incorporated

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

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