User's Manual

Page 19 of 83

A Carrier Corp. Company

PART NUMBER T82002163

REV A

9. The CAT5113 is a single digitally programmable 10K potentiometer designed as a electronic

replacement for mechanical potentiometers.

• The CAT5113 contains a 100-tap series resistor array connected between two terminals RH and

RL.

• An up/down counter and decoder that are controlled by three input pins, determines which tap is

connected to the wiper, RW.

• The wiper setting, stored in nonvolatile memory, is not lost when the device is powered down and

is automatically reinstated when power is returned.

• The wiper can be adjusted to test new system values without affecting the stored setting.

• Wiper-control of the CAT5113 is accomplished with three input control pins, /CS, U/D, and /INC.

• The /INC input increments the wiper in the direction which is determined by the logic state of the

U/D input.

• The /CS input is used to select the device and also store the wiper position prior to power down.

• The digitally programmable potentiometer can be used as a three-terminal resistive divider or as a

two terminal variable resistor.

During the event of transitioning the Chip Select from a low to a high state, this will Store the LCD

Contrast Voltage in Memory.

During the event of transitioning the Chip Select from a low to a high state and Increment low, this will not

store the value and return to standby.

(J1C.23 Card Engine) GPIO 99 = Up/Down

(J1C.88 Card Engine) GPIO 36 = Chip Select

(J1C.25 Card Engine) GPIO 27 = Increment

See block diagram below: