U3525A中文资料REGULATING PWM IC数据手册UTC规格书

描述 Description

The UTC U3525A is a pulse width modulator IC and designedfor switching power supplies application to improve performanceand reduce external parts usage.A shutdown terminal controls both the soft-start circuitry and theoutput stages, providing instantaneous turn off through the PWMlatch with pulsed shutdown, as well as soft-start recycle with longershutdown commands. The output stage

特性 Features

NOR logic, givinga LOW output for an OFF state. An under-voltage lockout circuitry,which keeps the outputs off and the soft-start capacitor dischargedfor sub-normal input voltages, includes approximately 500 mV ofhysteresis for jitter free operation. The PWM circuits also feature alatch following the comparator. When a PWM pulses has beenterminated, the outputs will remain off for the duration of the period.The latch is reset with each clock pulse. The output stages aretotem-pole designs capable of sourcing or sinking in excess of200mA. FEATURES  Input Voltage: 8~35V On-chip +5.1V reference is trimmed to ±1% 100HZ ~ 400KHZ oscillator range Separate oscillator sync terminal Adjustable dead time control Internal soft-start Pulse-by-pulse shutdown Input under-voltage lockout with hysteresis Latching PWM to prevent multiple pulses Dual source/sink output drivers