General Description
The Supertex HV9112 is a BiCMOS/DMOS single-output, pulse width modulator IC intended for use in high-speed, high-effi ciency switch mode power supplies. It provides all the functions necessary to implement a single-switch current mode PWM, in any topology, with a minimum of external parts.
Because the HV9112 utilizes Supertex’s proprietary BiCMOS/DMOS technology, it requires less than one tenth of the operating power of conventional bipolar PWM ICs, and can operate at more than twice their switching frequency. The dynamic range for regulation is also increased, to approximately 8 times that of similar bipolar parts. It starts directly from any DC input voltage between 10 and 120VDC, requiring no external power resistor. The output stage is push-pull CMOS and thus requires no clamping diodes for protection, even when signifi cant lead length exists between the output and the external MOSFET. The clock frequency is set with a single external resistor.

FEATUREs
► 10V to 120V Input Voltage Range
► Current-mode control
► High effi ciency
► Up to 1.0MHz internal oscillator
► Internal start-up circuit
► Low internal noise

APPLICATIONs
► DC/DC converters
► Distributed power systems
► ISDN equipment
► PBX systems
► Modems