LTC1840IGN

IC MOTOR CONTROLLER I2C 16SSOP

DESCRIPTION

The LTC® 1840 is a fan controller with two 8-bit current output DACs, two tachometer interfaces, and four general purpose I/O GPIO pins. It operates from a single supply with a range of 2.7V to 5.75V. A current output DAC is used to control an external switching regulator, which controls the fan speed. A current output DAC and tachometer allow a controller to form a closed control loop on fan velocity. The GPIO pins can be used as digital inputs or open drain pull-down outputs.

FEATURES

■ Two 8-Bit Current DACs

■ DACs Guaranteed Monotonic

■ Known IC State on Power-Up

■ Serial Interface Watchdog Timer with Disable

■ 2-Wire Serial Interface Compatible with I2C™and SMBus

■ 2 Programmable Fan Tachometer Interfaces

■ 4 Programmable General Purpose I/Os

■ Small 16-Pin SSOP Package

■ Single 2.7V to 5.75V Supply Operation

■ Fault Output Signal

■ Status Register

■ Fan Blasting Function

■ Nine Addresses Using Two Programming Lines