FUNCTIONAL BLOCK DIAGRAM
AGND
V
REF
V
IN
CLK
SAMPLE
D CHIP
AD677
RAM
ALU
SAR
AGND SENSE
CAL
BUSY
MICROCODED
CONTROLLER
A CHIP
LEVEL TRANSLATORS
LOGIC TIMING
INPUT
BUFFERS
COMP
DAC
CAL
16-BIT
DAC
10
9
11
8
16
2
1
15
3
14
SCLK
SDATA
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.
a
16-Bit 100 kSPS
Sampling ADC
AD677
FEATURES
Autocalibrating
On-Chip Sample-Hold Function
Serial Output
16 Bits No Missing Codes
61 LSB INL
–99 dB THD
92 dB S/(N+D)
1 MHz Full Power Bandwidth
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 Fax: 617/326-8703
PRODUCT HIGHLIGHTS
1. Autocalibration provides excellent dc performance while
eliminating the need for user adjustments or additional exter-
nal circuitry.
2. ±5 V to ±10 V input range (±V
REF
).
3. Available in 16-pin 0.3" skinny DIP or 28-lead SOIC.
4. Easy serial interface to standard ADI DSPs.
5. TTL compatible inputs/outputs.
6. Excellent ac performance: –99 dB THD, 92 dB S/(N+D)
peak spurious –101 dB.
7. Industry leading dc performance: 1.0 LSB INL, ±1 LSB full
scale and offset.
PRODUCT DESCRIPTION
The AD677 is a multipurpose 16-bit serial output analog-to-
digital converter which utilizes a switched-capacitor/charge
redistribution architecture to achieve a 100 kSPS conversion
rate (10 µs total conversion time). Overall performance is opti-
mized by digitally correcting internal nonlinearities through
on-chip autocalibration.
The AD677 circuitry is segmented onto two monolithic chips—
a digital control chip fabricated on Analog Devices DSP CMOS
process and an analog ADC chip fabricated on our BiMOS II
process. Both chips are contained in a single package.
The AD677 is specified for ac (or “dynamic”) parameters such
as S/(N+D) Ratio, THD and IMD which are important in sig-
nal processing applications. In addition, dc parameters are
specified which are important in measurement applications.
The AD677 operates from +5 V and ±12 V supplies and typi-
cally consumes 450 mW using a 10 V reference (360 mW with
5 V reference) during conversion. The digital supply (V
DD
) is
separated from the analog supplies (V
CC
, V
EE
) for reduced digi-
tal crosstalk. An analog ground sense is provided to remotely
sense the ground potential of the signal source. This can be use-
ful if the signal has to be carried some distance to the A/D con-
verter. Separate analog and digital grounds are also provided.
The AD677 is available in a 16-pin narrow plastic DIP, 16-pin
narrow side-brazed ceramic package, or 28-lead SOIC. A paral-
lel output version, the AD676, is available in a 28-pin ceramic
or plastic DIP. All models operate over a commercial tempera-
ture range of 0°C to +70°C or an industrial range of –40°C to
+85°C.
