a
FEATURES
Complete 10-Bit A/D Converter with Reference, Clock
and Comparator
Full 8- or 16-Bit Microprocessor Bus Interface
Fast Successive Approximation Conversion—20 s typ
No Missing Codes Over Temperature
Operates on +5 V and –12 V to –15 V Supplies
Low Cost Monolithic Construction
V+
5k
10-Bit A/D Converter
AD573*
FUNCTIONAL BLOCK DIAGRAM
V–
DIGITAL
COMMON
CONVERT
MSB
DB9
DB8
10-BIT
CURRENT
OUTPUT
DAC
COMP-
ARATOR
10-BIT
SAR
ANALOG
IN
ANALOG
COMMON
DB7
DB6
DB5
HIGH
BYTE
BIPOLAR
OFFSET
CONTROL
INT
CLOCK
DB4
DB3
DB2
DB1
DB0
LSB
HBE
LOW
BYTE
BURIED ZENER REF
DATA
READY
LBE
AD573
PRODUCT DESCRIPTION
The AD573 is a complete 10-bit successive approximation
analog-to-digital converter consisting of a DAC, voltage refer-
ence, clock, comparator, successive approximation register
(SAR) and three state output buffers—all fabricated on a single
chip. No external components are required to perform a full
accuracy 10-bit conversion in 20
µs.
The AD573 incorporates advanced integrated circuit design and
processing technologies. The successive approximation function
is implemented with I
2
L (integrated injection logic). Laser trim-
ming of the high stability SiCr thin-film resistor ladder network
insures high accuracy, which is maintained with a temperature
compensated subsurface Zener reference.
Operating on supplies of +5 V and –12 V to –15 V, the AD573
will accept analog inputs of 0 V to +10 V or –5 V to +5 V. The
trailing edge of a positive pulse on the CONVERT line initiates
the 20
µs
conversion cycle.
DATA READY
indicates completion
of the conversion.
HIGH BYTE ENABLE
(HBE) and
LOW
BYTE ENABLE
(LBE) control the 8-bit and 2-bit three state
output buffers.
The AD573 is available in two versions for the 0°C to +70°C
temperature range, the AD573J and AD573K. The AD573S
guarantees
±
1 LSB relative accuracy and no missing codes from
–55°C to +125°C.
Three package configurations are offered. All versions are offered
in a 20-pin hermetically sealed ceramic DIP. The AD573J and
AD573K are also available in a 20-pin plastic DIP or 20-pin
leaded chip carrier.
*Protected
by U.S. Patent Nos. 3,940,760; 4,213,806; 4,136,349; 4,400,689;
and 4,400,690.
PRODUCT HIGHLIGHTS
l. The AD573 is a complete 10-bit A/D converter. No external
components are required to perform a conversion.
2. The AD573 interfaces to many popular microprocessors
without external buffers or peripheral interface adapters. The
10 bits of output data can be read as a 10-bit word or as 8-
and 2-bit words.
3. The device offers true 10-bit accuracy and exhibits no miss-
ing codes over its entire operating temperature range.
4. The AD573 adapts to either unipolar (0 V to +10 V) or
bipolar (–5 V to +5 V) analog inputs by simply grounding or
opening a single pin.
5. Performance is guaranteed with +5 V and –12 V or –15 V
supplies.
6. The AD573 is available in a version compliant with MIL-STD-
883. Refer to the Analog Devices Military Products Data-
book or current /883B data sheet for detailed specifications.
REV. A
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
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