®
ADC674A
Microprocessor-Compatible
ANALOG-TO-DIGITAL CONVERTER
FEATURES
q
COMPLETE 12-BIT A/D CONVERTER
WITH REFERENCE, CLOCK, AND 8-, 12-,
OR 16-BIT MICROPROCESSOR BUS
INTERFACE
q
IMPROVED PERFORMANCE SECOND
SOURCE FOR ADC574A/674A-TYPE A/D
CONVERTERS
Conversion Time: 15
µ
s max
Bus Access Time:150ns max
A
0
Input: Bus Contention During Read
Operation Eliminated
q
FULLY SPECIFIED FOR OPERATION ON
±
12V OR
±
15V SUPPLIES
q
NO MISSING CODES OVER
TEMPERATURE:
0
°
C to +75
°
C ADC674AJH, KH, JP, KP
Grades
–55
°
C to +125
°
C (ADC674ASH, TH Grades)
DESCRIPTION
The ADC674A is a 12-bit successive approximation
analog-to-digital converter, utilizing state-of-the-art
CMOS and laser-trimmed bipolar die custom-designed
for freedom from latch-up and for optimum AC per-
formance. It is complete with a self-contained +10V
reference, internal clock, digital interface for micro-
processor control, and three-state outputs.
The reference circuit, containing a buried zener, is
laser-trimmed for minimum temperature coefficient.
The clock oscillator is current-controlled for excel-
lent stability over temperature. Full-scale and offset
errors may be externally trimmed to zero. Internal
scaling resistors are provided for the selection of
analog input signal ranges of 0V to +10V, 0V to
+20V,
±5V,
and
±10V.
The converter may be externally programmed to
provide 8- or 12-bit resolution. The conversion time
for 12 bits is factory set for 15µs maximum.
Output data are available in a parallel format from
TTL-compatible three-state output buffers. Output data
are coded in straight binary for unipolar input signals
and bipolar offset binary for bipolar input signals.
The ADC674A, available in both industrial and
military temperature ranges, requires supply voltages
of +5V and
±12V
or
±15V.
It is packaged in a 28-pin
plastic DIP, or hermetic side-brazed ceramic DIP.
Control
Inputs
Bipolar
Offset
20V Range
10V Range
Comparator
Control
Logic
Status
Successive
Approximation
Register
Clock
Three-State Buffers
12-Bit D/A
Converter
Reference
Input
Reference
Output
10V
Reference
Parallel
Data
Output
International Airport Industrial Park • Mailing Address: PO Box 11400 • Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706
Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
©
1984 Burr-Brown Corporation
PDS-551D
Printed in U.S.A. October, 1993
BURR-BROWN [ BURR-BROWN CORPORATION ]
