ZVS Full Bridge PWM Controller

The ISL6551 is a zero voltage switching (ZVS) full-bridge PWM controller designed for isolated power systems. This part implements a unique control algorithm for fixedfrequency ZVS current mode control, yielding high efficiency with low EMI. The two lower drivers are PWM-controlled on the trailing edge and employ resonant delay while the two upper drivers are driven at a fixed 50% duty cycle.

Features
• High Speed PWM (up to 1MHz) for ZVS Full Bridge Control
• Current Mode Control Compatible
• High Current High-Side and Low-Side Totem-Pole Drivers
• Adjustable Resonant Delay for ZVS
• 10MHz Error Amplifier Bandwidth
• Programmable Soft-Start
• Precision Bandgap Reference
• Latching Shutdown Input
• Non-latching Enable Input
• Adjustable Leading Edge Blanking
• Adjustable Dead Time Control
• Adjustable Ramp for Slope Compensation
• Fast Short-Circuit Protection (Hiccup Mode)
• Adjustable Cycle-by-Cycle Peak Current Limiting
• Drive Signals to Implement Synchronous Rectification
• VDD Under-voltage Lockout
• Current Share Support
• ±5% “In Regulation” Indication
• QFN Package:
    - Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat
        No Leads - Package Outline
    - Near Chip Scale Package footprint, which improves
        PCB efficiency and has a thinner profile
• Pb-Free Plus Anneal Available (RoHS Compliant)

Applications
• Full-Bridge and Push-Pull Converters
• Power Supplies for Off-line and Telecom/Datacom
• Power Supplies for High End Microprocessors and Servers