Datasheet Texas Instruments UC3578DP — Datenblatt

Not Recommended for New Designs UC2578
UC3578 application
INFO
available Buck Pulse Width Modulator Stepdown Voltage Regulator
FEATURES DESCRIPTION Provides Simple Single Inductor Buck
PWM Step-Down Voltage Regulation The UC3578 is a PWM controller with an integrated high side floating gate
driver. It is used in buck step down converters and regulates a positive
output voltage. Intended to be used in a distributed power system, the IC
allows operation from 14V to 72V input voltage which range includes the
prevalent telecomm bus voltages. The output duty cycle of the UC3578
can vary between 0% and 90% for operation over the wide input voltage
and load conditions. Drives External High Side NMOS
Switch 14V to 72V Input Voltage Operating
Range Contains 100kHz Internal Oscillator,
2V Reference and UVLO The UC3578 simplifies the design of the single switch PWM buck converter
by incorporating a floating high side driver for an external N-channel
MOSFET switch. It also features a 100kHz fixed frequency oscillator, an
internal 2V precision reference, an error amplifier configured for voltage
mode operation, and a PWM comparator with latching logic. Complementing the traditional voltage mode control block, the UC3578 incorporates an overcurrent shutdown circuit with full cycle soft re-start to limit the
input current to a user defined maximum value during overload operation.
Additional functions include an under voltage lockout circuit to insure that
sufficient input supply voltage is present before any switching activity can
occur. Soft Start on Power Up Overcurrent Shutdown Followed by …