a
FEATURES
Fast 16-Bit ADC
100 kSPS Throughput Rate—AD977
200 kSPS Throughput Rate—AD977A
Single 5 V Supply Operation
Power Dissipation 100 mW Max
Power-Down Mode 50 W
Input Ranges:
Unipolar; 0 V–10 V, 0 V–5 V and 0 V–4 V
Bipolar; ؎10 V, ؎5 V and ؎3.3 V
Choice of External or Internal 2.5 V Reference
High Speed Serial Interface
On-Chip Clock
20-Lead Skinny DIP or SOIC Package
28-Lead Skinny SSOP Package
16-Bit, 100 kSPS/200 kSPS
BiCMOS A/D Converter
AD977/AD977A
FUNCTIONAL BLOCK DIAGRAM
VANA
REF
4k⍀
AD977/
AD977A
2.5V
REFERENCE
CAP
4R
AGND1
R1IN
R2IN
R3IN
AGND2
VDIG
SYNC
2R
R
SWITCHED
CAP ADC
4R
SERIAL
DATA
INTERFACE
BUSY
DATACLK
DATA
R = 5k⍀ AD977
R = 2.5k⍀ AD977A
CONTROL LOGIC &
INTERNAL CALIBRATION CIRCUITRY
DGND
PWRD
R/C
CS
TAG
CLOCK
SB/BTC EXT/INT
GENERAL DESCRIPTION
PRODUCT HIGHLIGHTS
The AD977/AD977A is a high speed, low power 16-bit A/D
converter that operates from a single 5 V supply. The AD977A
has a throughput rate of 200 kSPS whereas the AD977 has a
throughput rate of 100 kSPS. Each part contains a successive
approximation, switched capacitor ADC, an internal 2.5 V
reference, and a high speed serial interface. The ADC is factory
calibrated to minimize all linearity errors. The AD977/AD977A is
specified for full scale bipolar input ranges of ± 10 V, ± 5 V and
± 3.3 V, and unipolar ranges of 0 V to 10 V, 0 V to 5 V and
0 V to 4 V.
1. Fast Throughput
The AD977/AD977A is a high speed, 16-bit ADC based on
a factory calibrated switched capacitor architecture.
The AD977/AD977A is comprehensively tested for ac parameters such as SNR and THD, as well as the more traditional dc
parameters of offset, gain and linearity.
2. Single-Supply Operation
The AD977/AD977A operates from a single 5 V supply and
dissipates only 100 mW max.
3. Comprehensive DC and AC Specifications
In addition to the traditional specifications of offset, gain
and linearity, the AD977/AD977A is fully tested for SNR
and THD.
REV. D
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: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2000
