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NEW PRODUCT NEWS—edited by John Gorsky

Predictive Fan Failure Circuit

The TC670 is the industryıs first predictive fan failure integrated circuit. A single resistor divider is adequate for setting the RPM alarm level and implementing predictive fan failure without the need for software. Eliminating the need to purchase more expensive and often custom-made 3-wire fans, the space-saving SOT-23 package has the ability to detect critical fan speed (RPM) of 2-wire and 3-wire fans and provide thermal failure protection in temperature-sensitive equipment.

The device is able to predict fan failure by sensing fan revolutions and asserting a logic-low alert signal whenever the fan speed falls below a user programmable trip point. The TC670 has a pin for clearing the alert signal, making it ideal for interfacing with microcontrollers. Hardware-based programmability allows for flexibility of design, since different systems utilize fans that run at different RPM levels, and reliability.

Small size and low operating current (90 mA typical) make the TC670 ideal for space and power critical systems. The TC670 also features high RPM detection accuracy as well as the ability to monitor multiple fans in parallel. This accuracy, flexibility, and software-free means of implementation significantly reduces the complexity and cost of predictive fan failure detection and therefore provides a superior, easy-to-use solution for equipment utilizing active cooling methods. Applications targeted for the TC670 device include telecom and networking equipment, power supplies, instrumentation, data storage equipment, notebooks and servers, industrial control and general-purpose fan-fault detection.

Pricing in 1000-unit quantities is $0.96 each for the TC670 (6-lead, SOT-23 package).

Microchip Technology, Inc.
(480) 792-7668
www.microchip.com.

03-02

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