NCP4302
Secondary Side
Synchronous Flyback
Controller
The NCP4302 is a full featured controller and driver that provide all
the control and protection functions necessary for implementing a
synchronous rectifier operation in a flyback converter. With the use of
the NCP4302, the space conscious flyback applications such as
Adaptors, chargers, set top boxes can achieve significant efficiency
improvements at minimal extra cost. In addition to the synchronous
rectifier control, the IC incorporates an accurate TL431 type shunt
regulator, current monitoring circuit and optocoupler driver to provide
a single IC secondary solution. The NCP4302 works with any type of
flyback topology (continuous mode, Quasi−resonant mode or
discontinuous mode) – providing a high level of versatility.
Features
• Self−contained Control of Synchronous Rectifier in CCM, DCM, and
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QR Flyback Applications
Interface to External Signal for CCM Mode
True Secondary Zero Current Detection
High Gate Drive Currents (2.5 A Source/Sink)
High Voltage Operation
Current Sense Flexibility (MOSFET RDS(on) OR CS Resistor)
Accurate Low Voltage Reference
− NCP4302A 2.55 V, 1%
− NCP4302B 1.275 V, 1%
Programmable Independent Secondary Side ton and toff Delays
Maximum Frequency of Operation up to 250 kHz
These are Pb−Free Devices
www.onsemi.com
MARKING
DIAGRAM
8
SO−8
D SUFFIX
CASE 751
8
1
x
A
L
Y
W
G
1
4302x
ALYW
G
= Reference Voltage (A or B)
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
PIN CONFIGURATION
SYNC/CS 1
8 VCC
TRIG 2
7 DRV
CATH 3
6 GND
VREF 4
5 DLYADJ
(Top View)
Typical Applications
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Notebook Adapters
LCD TV Adapters
Consumer Appliances such as DVD, VCR
Power Over Ethernet Applications (IP phones, Wireless Access
Points)
Battery Chargers
ORDERING INFORMATION
Device
Package
Shipping†
NCP4302ADR2G
SO−8
(Pb−Free)
2500/Tape & Reel
NCP4302BDR2G
SO−8
(Pb−Free)
2500/Tape & Reel
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specifications
Brochure, BRD8011/D.
© Semiconductor Components Industries, LLC, 2015
May, 2015 − Rev. 4
1
Publication Order Number:
NCP4302/D