ADS7844
12-Bit, 8-Channel Serial Output Sampling
ANALOG-TO-DIGITAL CONVERTER
FEATURES
l SINGLE SUPPLY: 2.7V to 5V
l 8-CHANNEL SINGLE-ENDED OR
4-CHANNEL DIFFERENTIAL INPUT
l UP TO 200kHz CONVERSION RATE
l – 1 LSB MAX INL AND DNL
l GUARANTEED NO MISSING CODES
l 72dB SINAD
l SERIAL INTERFACE
l 20-LEAD QSOP AND
20-LEAD SSOP PACKAGES
l ALTERNATE SOURCE FOR MAX147
®
DESCRIPTION
The ADS7844 is an 8-channel, 12-bit sampling ana-
log-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 (V
REF
) can be varied between 100mV
and V
CC
, providing a corresponding input voltage
range of 0V to V
REF
. The device includes a shutdown
mode which reduces power dissipation to under 1m W.
The ADS7844 is guaranteed down to 2.7V operation.
Low power, high speed, and on-board multiplexer
make the ADS7844 ideal for battery operated systems
such as personal digital assistants, portable multi-
channel 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 equiva-
lent 20-lead SSOP package and is guaranteed over the
–40 C to +85 C temperature range.
©
1998 Burr-Brown Corporation PDS-1463D Printed in U.S.A. July, 1999
APPLICATIONS
l DATA ACQUISITION
l TEST AND MEASUREMENT
l INDUSTRIAL PROCESS CONTROL
l PERSONAL DIGITAL ASSISTANTS
l 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
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Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
ADS7844
A
DS
7844