Datasheet

LTC2444/LTC2445/
LTC2448/LTC2449
7
2444589fc
For more information www.linear.com/LTC2444
pin FuncTions
CS (Pin 36): Active Low Chip Select. A LOW on this pin
enables the SDO digital output and wakes up the ADC.
Following each conversion the ADC automatically enters
the sleep mode and remains in this low power state as
long as CS is HIGH. A LOW-to-HIGH transition on CS dur
-
ing the Data Output aborts the data transfer and starts a
new conversion.
SDO (Pin 37)
: Three-State Digital Output. During the data
output period, this
pin is used as serial data output. When
the chip select CS is HIGH (CS = V
CC
) the SDO pin is in
a high impedance state. During the conversion and sleep
periods, this pin is used as the conversion status output.
The conversion status can be observed by pulling CS LOW.
This signal is HIGH while the conversion is in progress
and goes LOW once the conversion is complete.
SCK (Pin 38): Bidirectional Digital Clock Pin. In internal
serial clock operation mode, SCK is used as a digital
output for the internal serial interface clock during the
data output period. In the external serial clock operation
mode, SCK is used as the digital input for the external
serial interface clock during the data output period. The
serial clock operation mode is determined by the logic
level applied to the EXT pin.
Exposed Pad (Pin 39): Ground. The exposed pad on the
bottom of the package must be soldered to the PCB ground.
For prototyping purposes, this pin may remain floating.