DATASHEET ISL6745A FN6703 Rev.2.00 Improved Bridge Controller with Precision Dead Time Control Aug 14, 2017 The ISL6745A is a low-cost, double-ended, voltage-mode Features PWM controller designed for half-bridge and full-bridge Precision duty cycle and dead time control power supplies and line-regulated bus converters. It 100A start-up current provides precise control of switching frequency, adjustable soft-start, and overcurrent shutdown. In addition, the Adjustable delayed overcurrent shutdown and restart ISL6745A allows for accurate adjustment of MOSFET Adjustable oscillator frequency up to 2MHz non-overlap time (dead time) with dead times as low as 35ns, allowing power engineers to optimize the efficiency 1A MOSFET gate drivers of open-loop bus converters. The ISL6745A also includes a Adjustable soft-start control voltage input for closed-loop PWM and line voltage Internal over-temperature protection feed-forward functions. The ISL6745A is identical to the ISL6745, but is optimized for higher noise environments. 35ns control to output propagation delay Low start-up and operating currents allow for easy biasing Small size and minimal external component count in both AC/DC and DC/DC applications. This advanced Input undervoltage protection BiCMOS design also features adjustable switching frequency up to 1MHz, 1A FET drivers, and very low Pb-free (RoHS compliant) propagation delays for a fast response to overcurrent faults. Applications The ISL6745A is available in a space-saving 10 Ld MSOP Half-bridge converters package and is assured to meet rated specifications across a wide -40C to +105C temperature range. Full-bridge converters Related Literature Line-regulated bus converters For a full list of related documents, visit our website AC/DC power supplies ISL6745A product page Telecom, datacom, and file server power FN6703 Rev.2.00 Page 1 of 13 Aug 14, 2017ISL6745A 1. Overview FN6703 Rev.2.00 Page 2 of 13 Aug 14, 2017 1. Overview 1.1 Internal Architecture VDDP FL V BIAS V V BIAS DD 5.00V OUTA Q T UVLO + Q OUTB - PWM Toggle Internal VBIAS BG OT Shutdown 130C - 150C 70A GND ON SS V BIAS + SS Clamp - 15A R - TD 2.0V + SS Charged 3.9V IRTD - + 4.0V S Q V BIAS R Q 160A OC Latch ON - Peak 2.8V CLK S Q + R Q C T Q Reset - Valley Dominant Q SS Low + 0.27V 0.8V + 50s - Retriggerable One Shot SS Fault Latch Set Dominant S Q FL S Q I DCH R Q R Q PWM Latch ON V BIAS Set Dominant - VBIAS UV + 4.65V 4.80V BG OC Detect CS + - 0.6V PWM Comparator V BIA CT + S - - 15A V ERR SS 0.8 0.8 Figure 1. Internal Architecture I = 55 x DCH I RTD