Description

The IR2085S is a self-oscillating half-bridge driver IC with 50 duty cycle ideally suited for 36V – 75V half bridge DC-bus converters.

This product is also suitable for push-pull converters without restriction on input voltage.

Each channel frequency is equal to fOSC, which can be set by selecting RT & CT, where fOSC = 1/(2*RT.CT).

Dead-time can be controlled through proper selection of CT and can range from 50ns to 200ns. Internal soft-start increases the pulse width during power up and maintains pulse width matching for the high and low outputs throughout the start up cycle. The IR2085S initiates a soft start at power up and after every overcurrent condition. Undervoltage lockout prevents operation if VCC is less than 7.5V.

Features

• Simple primary side control solution to enable half-bridge DC-Bus

Converters for 48V distributed systems with reduced component

count and board space

• Integrated 50 duty cycle oscillator & half-bridge driver

IC in a single SO-8 package

• Programmable switching frequency with up to 500kHz max per channel

• +/- 1A drive current capability optimized for low charge MOSFETs

• Adjustable dead-time 50ns – 200ns

• Floating channel designed for bootstrap operation up to +100Vdc

• High and low side pulse width matching to +/- 25ns

• Adjustable overcurrent protection

• Undervoltage lockout and internal soft start

• Also available Leadfree