ADC7802
Autocalibrating, 4-Channel, 12-Bit
ANALOG-TO-DIGITAL CONVERTER
FEATURES
l TOTAL UNADJUSTED ERROR ≤ 1/2LSB
OVER FULL TEMPERATURE RANGE
l FOUR-CHANNEL INPUT MULTIPLEXER
l LOW POWER: 10mW plus Power Down
Mode
l SINGLE SUPPLY: +5V
l FAST CONVERSION TIME: 8.5µs Including
Acquisition
l AUTOCAL: No Offset or Gain Adjust
Required
l UNIPOLAR INPUTS: 0V to 5V
l MICROPROCESSOR-COMPATIBLE
INTERFACE
l INTERNAL SAMPLE/HOLD
DESCRIPTION
The ADC7802 is a monolithic CMOS 12-bit A/D
converter with internal sample/hold and four-channel
multiplexer. An autocalibration cycle, occurring auto-
matically at power on, guarantees a total unadjusted
error within ±1/2LSB 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
very easy to use in microprocessor applications. Con-
version results are available in two bytes through an 8-
bit three-state output bus.
The ADC7802 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.
Clock
Control
Logic
Calibration
Microcontroller
and Memory
Address
Latch and
Decoder
Analog
Multiplexer
Capacitor Array
Sampling ADC
Three-State
Input/Output
BUSY
8-Bit
Data Bus
V
REF
AIN0
AIN1
AIN2
AIN3
CS
RD
WR
SFR
V
REF
+–
A0
A1
®
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Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
© 1990 Burr-Brown Corporation PDS-1050B Printed in U.S.A. June, 1993