16-Bit, 100 kSPS/200 kSPS
BiCMOS A/D Converter
a
AD977/AD977A
FEATURES
FUNCTIONAL BLOCK DIAGRAM
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; ꢂ10 V, ꢂ5 V and ꢂ3.3 V
Choice of External or Internal 2.5 V Reference
High Speed Serial Interface
On-Chip Clock
V
REF
ANA
AGND1
4kꢀ
2.5V
AD977/
AD977A
CAP
REFERENCE
4R
2R
R
R1
R2
R3
IN
IN
IN
SYNC
SERIAL
DATA
BUSY
DATACLK
SWITCHED
CAP ADC
4R
INTERFACE
DATA
R = 5kꢀ AD977
R = 2.5kꢀ AD977A
AGND2
CONTROL LOGIC &
V
DIG
CLOCK
INTERNAL CALIBRATION CIRCUITRY
20-Lead Skinny DIP or SOIC Package
28-Lead Skinny SSOP Package
DGND PWRD
R/C
CS
TAG 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.
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.
The AD977/AD977A is comprehensively tested for ac param-
eters such as SNR and THD, as well as the more traditional dc
parameters of offset, gain and linearity.
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.
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Tel: 781/329-4700
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© Analog Devices, Inc., 2000