SPI接口Microchip的风扇速度控制器

Microchip'sTC642,TC643,andTC646aretheworld'sfirstinte-

gratedcircuitsdedicatedforcontrollingandmonitoringfanspeed.

Thenewfamilyoffanspeedcontrollersmodulatefanspeedto

compensateforchangesinsystemtemperature.Thismeansthe

fanrunsatfullspeedonlywhennecessary,significantlyextending

fanlife.Inadditiontoincreasedfanlife,fanspeediscontrolledby

PWMcontrolcircuitrythatismoreefficientthanconventionallinear

techniques.TheICsprovideotherfeaturessuchasfancurrent

limiting,minimumspeedcontrol,autoshutdown,andspeed,fault,

andover-temperatureindication.AN767InterfacingMicrochip'sFanSpeedControllerstoaSPIPortAuthor:PaulPaglia,STANDARDIMPLEMENTATIONMicrochipTechnology,Inc.TheTC642,TC643,andTC646usetwodifferentmethodologiestocontrolfanspeed.TheTC642/646provideastandalonesolutionwhereastheTC643requiresanexternaldrivesignalandRPMINTRODUCTIONs