NCP4302 Datasheet, PDF (1/16 Pages) ON Semiconductor – Secondary Side Synchronous Flyback Controller

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
•ăSelf-contained Control of Synchronous Rectifier in CCM, DCM, and
QR Flyback Applications
•ăInterface to External Signal for CCM Mode
•ăTrue Secondary Zero Current Detection
•ăHigh Gate Drive Currents (2.5 A Source/Sink)
•ăHigh Voltage Operation
•ăCurrent Sense Flexibility (MOSFET R_DS(on) OR CS Resistor)
•ăAccurate Low Voltage Reference
- NCP4302A 2.55 V, 1%
- NCP4302B 1.275 V, 1%
•ăProgrammable Independent Secondary Side t_on and t_off Delays
•ăMaximum Frequency of Operation up to 250 kHz
•ăThese are Pb-Free Devices
Typical Applications
•ăNotebook Adapters
•ăLCD TV Adapters
•ăConsumer Appliances such as DVD, VCR
•ăPower Over Ethernet Applications (IP phones, Wireless Access
Points)
•ăBattery Chargers
http://onsemi.com
8
1
SO-8
D SUFFIX
CASE 751
MARKING
DIAGRAM
8
4302x
ALYW
G
1
x
= Reference Voltage (A or B)
A
= Assembly Location
L
= Wafer Lot
Y
= Year
W = Work Week
G
= Pb-Free Package
PIN CONFIGURATION
SYNC/CS 1
TRIG ²
CATH 3
V_REF ⁴
8 V_CC
7 DRV
6 GND
5 D_LYADJ
(Top View)
ORDERING INFORMATION
Device
Package
Shipping^†
NCP4302ADR2G SO-8 2500/Tape & Reel
(Pb-Free)
NCP4302BDR2G SO-8 2500/Tape & Reel
(Pb-Free)
†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.
©Ă Semiconductor Components Industries, LLC, 2008
1
February, 2008 - Rev. 2
Publication Order Number:
NCP4302/D