Five new devices offer solution to extend fan life, reduce acoustic noise and increase system reliability
May 15, 2003- Microchip Technology Inc. announced the expansion of its fan-speed control and fan-fault detection family featuring a proprietary fan auto-restart functionality.
This fan-restart functionality enables the device to continuously initiate a restart during a fan-fault condition. This simplifies system design by eliminating the need for resetting the fan after a fan-fault condition occurs. The TC64xB devices also enable the user to set a minimum fan speed threshold (TC642B and TC647B) or an auto-shutdown threshold (TC646B, TC648B, and TC649B) to control fan operation when the operating temperature falls to lower levels. In addition, the TC642/6/8B devices assert an over-temperature signal to indicate a possible over-heating condition.
Ideal for telecom and networking equipment, power supplies, office equipment, notebooks and servers, Microchip's TC64xB family of fan managers and fan-health monitors adjust fan speed according to temperature instead of continuously running a system's fan at maximum speed. Since the fan only runs as fast as necessary, the life of the fan is extended and the acoustic noise is reduced. Moreover, this family of devices detects when a fan locks up and launches an alert signal to the host processor. This enables the user to replace the fan in time or shut down the system, therefore, eliminating any thermal issues that can impact the systems performance and reliability.
Integrating FanSenseTM technology, the devices enable designers to use
2-wire fans, therefore, eliminating the need to purchase more expensive 3-wire
fans. The FanSense technology is Microchip's patented design implementation
of sensing when fan current pulses are present, thus detecting fan-fault conditions
and protecting against fan failure, while aiding in system testing.
The TC64xB family utilizes an external power device enabling design flexibility
and allowing the devices to drive 5-, 12-, 24- and 48-volt fans rated up to
1 amp. Unlike linear regulation, the efficient pulse-width modulation (PWM)
fan-drive leads to low-power dissipation.
These devices have an operating voltage range of 3.0V to 5.5V, an extended temperature range of -40oC to +85oC and are available in an 8-pin MSOP, SOIC and PDIP package. Available in quantities of 1,000-units, these devices are priced at $1.06 each for the TC647B, TC648B, and TC649B and $1.12 each for the TC642B and the TC646B.
