HF900GS datasheet(11/25 Pages) MPS

11 / 25 page

HF900 – 900V OFFLINE SWITCHING REGULATOR

HF900 Rev. 1.0

www.MonolithicPower.com

8/4/2015

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

PIN FUNCTIONS

Pin #

PDIP8-7EP

Pin #

SOIC14-11

Name

Description

Feedback. The output voltage from the external compensation circuit

is fed into this pin. FB and the current sense signal from SOURCE

determines the PWM duty cycle. A feedback voltage of VOLP triggers

overload protection while VBURL triggers burst-mode operation. The

regulator exits burst-mode operation and enters normal operation

when the FB voltage reaches VBURH.

PRO

Input over-voltage protection. When voltage on PRO rises to VPRO,

the IC is shut down with hysteresis.

FSET

Switching converter frequency set. Connect a resistor to GND to

set the switching frequency up to 300kHz.

VCC

Supply voltage. Connect a 22μF bulk capacitor and a 0.1µF ceramic

capacitor for most applications. When VCC rises to VCCH, the IC starts

switching; when it falls below VCCL, the IC stops switching.

DRAIN

Drain of the internal MOSFET. Input for the start-up high-voltage

current source.

SOURCE

Source of the internal MOSFET. Input of the primary current sense

signal.

1,2,7,8

GND

IC ground.

Not connected.

HF900GS Datasheet(PDF) 11 Page - Monolithic Power Systems