MAX6684

19-2306; Rev 0; 1/02 Fan-Failure Detector with Integrated Power Switch General Description The MAX6684 is an integrated fan-failure detector that detects when a fan exhibits excessive underspeed or a locked rotor. This device is especially well suited for critical systems where no fan control, or simple on/off control is desired. The MAX6684 detects fan failure by evaluating fluctuations in current at the low side of the fan; no tachometer signal is necessary. The output of the device, FAIL, is an active-low, open-drain alarm. The MAX6684 can also be used to switch the fan on or off, based on the state of a logic-level input, OFF. This device can be used with fans rated at up to 24V and 250mA. The MAX6684 is available in an 8-pin SO package, and is specified for operation from -40°C to +85°C. o Dedicated Fan-Failure Detector o Works with Ordinary 2-Wire Fans o No Fan Tachometer Output Required o No Software Development Required o No Analog Circuit Design Required o Logic-Level Fan Driver Control o Works with Fans Rated Up to 24V/250mA Features MAX6684 Applications Desktop PCs Notebooks Networking Equipment Telecommunications Industrial Applications PART MAX6684ESA Ordering Information TEMP RANGE -40°C to +85°C PIN-PACKAGE 8 SO Typical Operating Circuit 3.3V Pin Configuration TOP VIEW 12V VCC OFF 10kΩ SENSE 1 FAIL 2 8 7 PGND OFF VCC FC+ MAX6684 FC+ 1µF 0.1µF FCGND SENSE PGND 0.1µF FAIL MAX6684 GND 3 6 5 FC- 4 SO __________________________________________________...