NCP4305 Secondary Side Synchronous Rectification Driver for High Efficiency SMPS Topologies www.onsemi.com The NCP4305 is high performance driver tailored to control a synchronous rectification MOSFET in switch mode power supplies. Thanks to its high performance drivers and versatility, it can be used in MARKING various topologies such as DCM or CCM flyback, quasi resonant DIAGRAMS flyback, forward and half bridge resonant LLC. 8 8 The combination of externally adjustable minimum off-time and NCP4305x 1 on-time blanking periods helps to fight the ringing induced by the PCB ALYW SOIC8 layout and other parasitic elements. A reliable and noise less operation D SUFFIX CASE 751 of the SR system is insured due to the Self Synchronization feature. The 1 NCP4305 also utilizes Kelvin connection of the driver to the MOSFET to achieve high efficiency operation at full load and utilizes a light load detection architecture to achieve high efficiency at light load. 1 4305x The precise turnoff threshold, extremely low turnoff delay time ALYW DFN8 and high sink current capability of the driver allow the maximum MN SUFFIX synchronous rectification MOSFET conduction time and enables CASE 488AF maximum SMPS efficiency. The high accuracy driver and 5 V gate clamp enables the use of GaN FETs. 1 Features 5xM SelfContained Control of Synchronous Rectifier in CCM, DCM and WDFN8 MT SUFFIX QR for Flyback, Forward or LLC Applications CASE 511AT Precise True Secondary Zero Current Detection 4305x = Specific Device Code Typically 12 ns Turn off Delay from Current Sense Input to Driver x = A, B, C, D or Q Rugged Current Sense Pin (up to 200 V) A = Assembly Location Ultrafast Turnoff Trigger Interface/Disable Input (7.5 ns) L = Wafer Lot Y = Year Adjustable Minimum ONTime W = Work Week Adjustable Minimum OFF-Time with Ringing Detection M = Date Code = PbFree Package Adjustable Maximum ONTime for CCM Controlling of Primary QR Controller (Note: Microdot may be in either location) Improved Robust Self Synchronization Capability ORDERING INFORMATION 8 A / 4 A Peak Current Sink / Source Drive Capability See detailed ordering and shipping information on page 49 of Operating Voltage Range up to V = 35 V CC this data sheet. Automatic Lightload & Disable Mode Typical Applications Adaptive Gate Drive Clamp Notebook Adapters GaN Transistor Driving Capability (options A and C) High Power Density AC/DC Power Supplies (Cell Low Startup and Disable Current Consumption Phone Chargers) Maximum Operation Frequency up to 1 MHz LCD TVs SOIC-8 and DFN8 (4x4) and WDFN8 (2x2) Packages All SMPS with High Efficiency Requirements These are PbFree Devices Semiconductor Components Industries, LLC, 2016 1 Publication Order Number: June, 2016 Rev. 3 NCP4305/DNCP4305 Figure 1. Typical Application Example LLC Converter with Optional LLD and Trigger Utilization Figure 2. Typical Application Example DCM, CCM or QR Flyback Converter with optional LLD and Disabled TRIG www.onsemi.com 2