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, where fosc 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 50 to 200nsec. 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 7.5Vdc.

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 50nsec – 200nsec
• Floating channel designed for bootstrap operation up to +100Vdc
• High and low side pulse width matching to +/- 25nsec
• Adjustable overcurrent protection
• Undervoltage lockout and internal soft start
• Also available LEAD-FREE