®
ADS7803
Autocalibrating, 4-Channel, 12-Bit
ANALOG-TO-DIGITAL CONVERTER
FEATURES
q
LOW POWER: 10mW plus Power Down
q
SIGNAL-TO-(NOISE + DISTORTION)
RATIO OVER TEMPERATURE:
69dB min with f
IN
= 1kHz
66dB min with f
IN
= 50kHz
q
FAST CONVERSION TIME: 8.5
µ
s
Including Acquisition (117kHz Sampling
Rate)
q
DC PERFORMANCE OVER
TEMPERATURE:
±
3/4 LSB max Total Error
±
1/4 LSB max Channel Mismatch
q
FOUR-CHANNEL INPUT MULTIPLEXER
q
SINGLE SUPPLY: +5V
q
PIN COMPATIBLE WITH ADC7802
DESCRIPTION
The ADS7803 is a monolithic CMOS 12-bit analog-
to-digital converter with internal sample/hold and four-
channel multiplexer. It is designed and tested for full
dynamic performance with input signals to 50kHz. An
autocalibration cycle guarantees a total unadjusted
error within
±3/4LSB
over the specified temperature
range, eliminating the need for offset or gain adjust-
ment. The 5V single-supply requirements and stan-
dard CS, RD, and WR control signals make the part
easy to use in microprocessor applications. Conver-
sion results are available in two bytes through an 8-bit
three-state output bus.
The ADS7803 is available in a 28-pin plastic DIP and
28-lead PLCC, fully specified for operation over the
industrial –40°C to +85°C temperature range.
A0
A1
Address
Latch and
Decoder
Calibration
Microcontroller
and Memory
Clock
Control
Logic
CS
RD
WR
SFR
AIN0
AIN1
AIN2
AIN3
Analog
Multiplexer
Capacitor Array
Sampling ADC
Three-State
Input/Output
BUSY
8-Bit
Data Bus
V
REF
+
V
REF
–
International Airport Industrial Park • Mailing Address: PO Box 11400
Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP •
©
• Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706
Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
PDS-1126A
Printed in U.S.A. August, 1993
1991 Burr-Brown Corporation