FUNCTIONAL BLOCK DIAGRAM
AGND
V
DD
DGND SCLK
CONVST
AD7893
V
IN
SDATA
REF IN
TRACK/
HOLD
*AD7893-5, AD7893-10, AD7893-3
SIGNAL
SCALING*
12-BIT
ADC
OUTPUT
REGISTER
REV. E
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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.
a
LC
2
MOS 12-Bit, Serial 6 ms
ADC in 8-Pin Package
AD7893
FEATURES
Fast 12-Bit ADC with 6 ms Conversion Time
8-Pin Mini-DlP and SOIC
Single Supply Operation
High Speed, Easy-to-Use, Serial Interface
On-Chip Track/Hold Amplifier
Selection of Input Ranges
610 V for AD7893-10
62.5 V for AD7893-3
0 V to +2.5 V for AD7893-2
0 V to +5 V for AD7893-5
Low Power: 25 mW typ
GENERAL DESCRIPTION
The AD7893 is a fast, 12-bit ADC that operates from a single
+5 V supply and is housed in a small 8-pin mini-DIP and 8-pin
SOIC. The part contains a 6 µs successive approximation A/D
converter, an on-chip track/hold amplifier, an on-chip clock and
a high speed serial interface.
Output data from the AD7893 is provided via a high speed,
serial interface port. This two-wire serial interface has a serial
clock input and a serial data output with the external serial clock
accessing the serial data from the part.
In addition to traditional dc accuracy specifications such as lin-
earity, full-scale and offset errors, the AD7893 is also specified
for dynamic performance parameters, including harmonic dis-
tortion and signal-to-noise ratio.
The part accepts an analog input range of ±10 V (AD7893-10),
±2.5 V (AD7893-3), 0 V to +5 V (AD7893-5) or 0 V to +2.5 V
(AD7893-2) and operates from a single +5 V supply, consuming
only 25 mW typical.
The AD7893 is fabricated in Analog Devices’ Linear Compat-
ible CMOS (LC
2
MOS) process, a mixed technology process
that combines precision bipolar circuits with low power CMOS
logic. The part is available in a small, 8-pin, 0.3" wide, plastic or
hermetic dual-in-line package (mini-DIP) and in an 8-pin, small
outline IC (SOIC).
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 World Wide Web Site: http://www.analog.com
Fax: 617/326-8703 © Analog Devices, Inc., 1997
PRODUCT HIGHLIGHTS
1. Fast, 12-Bit ADC in 8-Pin Package
The AD7893 contains a 6 µs ADC, a track/hold amplifier,
control logic and a high speed serial interface, all in an 8-pin
package. This offers considerable space saving over alterna-
tive solutions.
2. Low Power, Single Supply Operation
The AD7893 operates from a single +5 V supply and con-
sumes only 25 mW. This low power, single supply operation
makes it ideal for battery powered or portable applications.
3. High Speed Serial Interface
The part provides high speed serial data and serial clock lines,
allowing for an easy, two-wire serial interface arrangement.
