FSCT07A-UH5

® FSCTxxA-UH5 A.S.D.TM Application Specific Discretes FAN SPEED CONTROLER APPLICATIONS COMPUTER AND SERVER POWER SUPPLY TELECOM LOW COST VENTILATION (consumer) s s s FEATURES Built in thermal sensor Brushless DC fan speed control Linear control and regulation of the fan speed according to the temperature Green OFF mode operation with automatic turn- ON in case of overtemperature Voltage limitation above fan stall voltage No external NTC required s s s s s s 5 1 IPPAK Fig. 1: Block Diagram. ON BENEFITS Low cost integrated fan speed control High integration: only one or two external components Reduced acoustic noise because of the linear control of the external transistor Power supply noise rejection Good thermal coupling with heater Reduced ON/OFF oscillation because of large hysteresis High current capability (base current higher than 10 mA) Higher accuracy than discrete circuit with NTC s s s s s s s s BIAS FSCTxxA-UH5 F VCC VOLTAGE REF. ON/OFF LOW HYSTERESIS COMPARATOR HYST.-EN ON/OFF HIGH ON REGULATION OUT TEMP. SENSOR VT DRIVER COUT= 100nF GND GENERAL DESCRIPTION The FSCTxxA-UH5 is a high-integrated low cost fan speed controller suitable for PC desktops, notebooks and server power supplies and also all kind of equipments where low cost ventilation system is needed. An internal thermal sensor connected to the tab is used to regulate the fan speed. A continuous analog voltage proportional to the tab temperature is produced at the OUT terminal and can contro...