18-Bit, 670 kSPS, Differential
Programmable Input PulSAR® ADC
AD7634 Data Sheet
FEATURES FUNCTIONAL BLOCK DIAGRAM
TEMP REFBUFIN REF REFGND VCC VEE DVDD
AGND PDREF GENERAL DESCRIPTION
The AD7634 is an 18-bit charge redistribution successive
approximation register (SAR), architecture analog-todigital converter (ADC) fabricated on Analog Devices, Inc.’s
iCMOS high voltage process. The device is configured through
hardware or via a dedicated write-only serial configuration port
for input range and operating mode. The AD7634 contains a
high speed 18-bit sampling ADC, an internal conversion clock,
an internal reference (and buffer), error correction circuits, and
both serial and parallel system interface ports. A falling edge on
CNVST samples the fully differential analog inputs on IN+ and
IN−. The AD7634 features four different analog input ranges and
three different sampling modes. Operation is specified from
−40°C to +85°C.
Rev. B SERIAL
CONFIGURATION
18
PORT PDBUF
IN+ SWITCHED …