Block Diagram
20132702
Pin Descriptions and Equivalent Circuits
Pin No. Symbol Description
1V
REF
Reference Voltage input.
2 +IN Non-inverting input.
3 −IN Inverting input.
4 GND Ground pin.
5CS
The ADC is in the active move when this pin is LOW and in
the Power-Down Mode when this pin is HIGH. A conversion
begins at the fall of CS.
6D
OUT
The serial output data word is comprised of 12 bits of data. In
operation the data is valid on the falling edge of SCLK. The
second clock pulse after the falling edge of CS enables the
serial output. After one null bit the data is valid for the next 12
SCLK edges.
7 SCLK
Serial Clock used to control data transfer. Also serves as the
conversion clock.
8V
A
Power Supply input.
ADC121S625
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