DATASHEET ISL78223 FN7936 Rev.4.00 ZVS Full-Bridge PWM Controller with Adjustable Synchronous Rectifier Control May 8, 2017 The ISL78223 is a high performance Zero Voltage Switching Features (ZVS) full-bridge PWM controller. It achieves ZVS operation by Adjustable resonant delay for ZVS operation driving the upper bridge FETs at a fixed 50% duty cycle while the lower bridge FETs are trailing-edge modulated with Synchronous rectifier control outputs with adjustable adjustable resonant switching delays. delay/advance Adding to the ISL78223s feature set are average current Voltage or current mode control monitoring and soft-start. The average current signal can be 3% current limit threshold used for average current limiting, current sharing circuits, and Adjustable average current limit average current mode control. Additionally, the ISL78223 supports both voltage and current mode control. Adjustable deadtime control 175A start-up current The ISL78223 features complemented PWM outputs for Synchronous Rectifier (SR) control. The complemented Supply UVLO outputs can be dynamically advanced or delayed relative to the Adjustable oscillator frequency up to 2MHz PWM outputs using an external control voltage. Internal over-temperature protection This advanced BiCMOS design features precision deadtime Buffered oscillator sawtooth output and resonant delay control and an oscillator adjustable to 2MHz operating frequency. Additionally, Multi-Pulse Fast current sense to output delay Suppression ensures alternating output pulses at low duty Adjustable cycle-by-cycle peak current limit cycles where pulse skipping may occur. 70ns leading edge blanking The ISL78223 is rated for the automotive temperature range Multi-pulse suppression (-40C to +105C). Pb-free (RoHS compliant) Related Literature Applications For a full list of related documents, visit our website ZVS full-bridge converters - ISL78223 product page Telecom and datacom power Wireless base station power File server power Industrial power systems 10.0 0.95 0.90 0.85 V = 250V IN 0.80 V = 350V IN 0.75 V = 450V IN 0.70 V = 13.1V O 0.65 0 20 40 60 80 100 LOAD (0-125A) (%) FIGURE 2. EFFICIENCY vs LOAD FIGURE 1. BOARD LAYOUT FN7936 Rev.4.00 Page 1 of 20 May 8, 2017 EFFICIENCYISL78223 FN7936 Rev.4.00 Page 2 of 20 May 8, 2017 Functional Block Diagram VDD OUTUL 50% OUTUR VDD VREF PWM DELAY/ UVLO STEERING ADVANCE OUTLL LOGIC TIMING CONTROL OUTLR PWM OVER- TEMPERATURE PROTECTION OUTLLN OUTLRN GND VREF VADJ SAMPLE AND RESDEL + CS HOLD - 1.00V +70ns IOUT 4X LEADING EDGE OVERCURRENT BLANKING COMPARATOR OSCILLATOR CT VREF RTD RAMP VREF PWM COMPARATOR 80mV 1mA CTBUF + - SS 0.33 VERR + 0.6V SOFT-START CONTROL - FB FIGURE 3. BLOCK DIAGRAM