FUNCTIONAL BLOCK DIAGRAM
REF OUT
SHA
COMP
20k
10k
5k
2.5k
2.5k
5k
12
12
AD1674
AGND
BIP OFF
REF IN
20V
IN
10V
IN
IDAC
12
CONTROL
CE
12/8
CS
R/C
A
0
5k
10k
SAR
CLOCK
10V
REF
REGISTERS / 3-STATE OUTPUT BUFFERS
DAC
STS
DB11 (MSB)
DB0 (LSB)
REV. C
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
12-Bit 100 kSPS
A/D Converter
AD1674*
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 Fax: 617/326-8703
FEATURES
Complete Monolithic 12-Bit 10 ms Sampling ADC
On-Board Sample-and-Hold Amplifier
Industry Standard Pinout
8- and 16-Bit Microprocessor Interface
AC and DC Specified and Tested
Unipolar and Bipolar Inputs
65 V, 610 V, 0 V–10 V, 0 V–20 V Input Ranges
Commercial, Industrial and Military Temperature
Range Grades
MIL-STD-883 and SMD Compliant Versions Available
PRODUCT DESCRIPTION
The AD1674 is a complete, multipurpose, 12-bit analog-to-
digital converter, consisting of a user-transparent onboard
sample-and-hold amplifier (SHA), 10 volt reference, clock and
three-state output buffers for microprocessor interface.
The AD1674 is pin compatible with the industry standard
AD574A and AD674A, but includes a sampling function while
delivering a faster conversion rate. The on-chip SHA has a wide
input bandwidth supporting 12-bit accuracy over the full
Nyquist bandwidth of the converter.
The AD1674 is fully specified for ac parameters (such as S/(N+D)
ratio, THD, and IMD) and dc parameters (offset, full-scale
error, etc.). With both ac and dc specifications, the AD1674 is
ideal for use in signal processing and traditional dc measure-
ment applications.
The AD1674 design is implemented using Analog Devices’
BiMOS II process allowing high performance bipolar analog cir-
cuitry to be combined on the same die with digital CMOS logic.
Five different temperature grades are available. The AD1674J
and K grades are specified for operation over the 0°C to +70°C
temperature range. The A and B grades are specified from
–40°C to +85°C; the AD1674T grade is specified from –55°C
to +125°C. The J and K grades are available in both 28-lead
plastic DIP and SOIC. The A and B grade devices are available
in 28-lead hermetically sealed ceramic DIP and 28-lead SOIC.
The T grade is available in 28-lead hermetically sealed ceramic
DIP.
*Protected by U. S. Patent Nos. 4,962,325; 4,250,445; 4,808,908; RE30586.
PRODUCT HIGHLIGHTS
1. Industry Standard Pinout: The AD1674 utilizes the pinout
established by the industry standard AD574A and AD674A.
2. Integrated SHA: The AD1674 has an integrated SHA which
supports the full Nyquist bandwidth of the converter. The
SHA function is transparent to the user; no wait-states are
needed for SHA acquisition.
3. DC and AC Specified: In addition to traditional dc specifica-
tions, the AD1674 is also fully specified for frequency do-
main ac parameters such as total harmonic distortion,
signal-to-noise ratio and input bandwidth. These parameters
can be tested and guaranteed as a result of the onboard
SHA.
4. Analog Operation: The precision, laser-trimmed scaling and
bipolar offset resistors provide four calibrated ranges:
0 V to +10 V and 0 V to +20 V unipolar, –5 V to +5 V and
–10 V to +10 V bipolar. The AD1674 operates on +5 V and
±12 V or ±15 V power supplies.
5. Flexible Digital Interface: On-chip multiple-mode
three-state output buffers and interface logic allow direct
connection to most microprocessors.
