Advanced Synchronous
Rectifier Controller for LLC
Resonant Converter
NCP4318
NCP4318 is an advanced synchronous rectification (SR) controller
for LLC resonant converter with minimum external components. It
has two gate driver stages for driving the SR MOSFETs which are
rectifying the outputs of the secondary transformer windings. The two
gate driver stages have their own Drain and Source sensing inputs and
operate independently of each other. The advanced adaptive dead time
control compensates a voltage across parasitic inductance to minimize
the body diode conduction and maximize the system efficiency. The
advanced turn−off control algorithm allows stable SR operation over
entire load range. NCP4318 has two versions of pin assignment –
NCP4318AXX, NCP4318BXX.
www.onsemi.com
SOIC 8, 150 mils
CASE 751BD
MARKING DIAGRAM
Features
8
• Mixed Mode SR Turn−off Control
• Anti Shoot−through Control for Reliable SR Operation
NCP4318
UVW
AWLYYWW
• Separate 200 V Rated Sense Pins for the Drain and Dedicated Source
1
Sense Pins
• Advanced Adaptive Dead Time Control
• SR Current Inversion Detection
U
V
W
A
= Pin Layout, A and B
= Frequency, H: High, L: Low
= Additional IPT option
= Assembly Location
• Adaptive Minimum Turn−on Time for Noise Immunity
• SR Conduction Time Increase Rate Limitation
• Multi−level Turn−off Threshold Voltage
WL = Wafer Lot Traceability
YYWW = Date Code
• Adaptive Gate Voltage Control (10 V, 6 V)
PIN CONNECTIONS
• Low Operating Current (100 mA) in Green Mode
• Soft Start for 512 Switching Cycle with 0 V/6 V Gate Output Voltage
• Very Fast Turn−on and Turn−off Delay Time (30 ns/30 ns)
• Large Gate Sourcing and Sinking Current (1.5 A/4.5 A)
• Wide Operating Supply Voltage Range from 6.5 V to 35 V
• Wide Operating Frequency Range (22 kHz to 500 kHz)
• SOIC−8 Package
NCP4318AXX
GATE1
GND
VS1
GATE2
VDD
VD2
VD1
VS2
• These Devices are Pb−Free and are RoHS Compliant
NCP4318BXX
Applications
• High Power Density Adapters
• Large Screen LED−TV and OLED−TV Power Supplies
• High Efficiency Desktop and Server Power Supplies
• Networking and Telecom Power Supplies
• High Power LED Lighting
GATE1
GND
VD1
GATE2
VDD
VD2
VS1
VS2
(Top View)
ORDERING INFORMATION
See detailed ordering, marking and shipping information on
page 3 of this data sheet.
© Semiconductor Components Industries, LLC, 2020
1
Publication Order Number:
March, 2021 − Rev. 1
NCP4318/D