APR34309CA Datasheet, PDF (1/11 Pages) Diodes Incorporated – SECONDARY SIDE SYNCHRONOUS RECTIFICATION SWITCHER

APR34309CA
SECONDARY SIDE SYNCHRONOUS RECTIFICATION SWITCHER
Description
APR34309CA is a secondary side Combo IC, which combines an N-
Channel MOSFET and a driver circuit designed for synchronous
rectification (SR) in DCM operation. It also integrates output voltage
detect function for primary side control system.
The N-Channel MOSFET has been optimized for low gate charge,
low RDS(ON), fast switching speed and body diode reverse recovery
performance.
The synchronous rectification can effectively reduce the secondary
side rectifier power dissipation and provide high performance solution.
By sensing MOSFET drain-to-source voltage, APR34309CA can
output ideal drive signal with less external components. It can provide
high performance solution for 5V output voltage application.
Same as AP4341, APR34309CA detects the output voltage and
provides a periodical signal when the output voltage is lower than a
certain threshold. By fast response to secondary side voltage,
APR34309CA can effectively improve the transient performance of
primary side control system.
The APR34309CA is available in SO-8EP package.
Pin Assignments
(Top View)
DRISR ₁
VDET 2
AREF ₃
VCC ₄
8 ^GND
7 ^GND
6 ^GND
5 DRAIN
Note: The DRAIN pin of internal MOSFET is exposed PAD, which is at the bottom
of IC (the dashed box). The secondary current should flow from GND(pin 6,7,8) to
this exposed PAD.
SO-8EP
Applications
Features
• Synchronous Rectification for DCM Operation Flyback
• Eliminate Resonant Ring Interference
• Fast Detector of Supply Voltages
• Fewest External Components
 Totally Lead-free & Fully RoHS Compliant (Notes 1 & 2)
 Halogen and Antimony Free. “Green” Device (Note 3)
• Adapters/Chargers for Cell/Cordless Phones, ADSL Modems, MP3
and Other Portable Apparatus
• Standby and Auxiliary Power Supplies
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
Typical Applications Circuit
C23 _R21
C21 C22
++
APR34309CA
R23
DRAINDRAIN ^GND
DRISR
GND
VDET
GND
C_AREF
AREF
R_AREF
VCC
R24
C24
APR34309CA
Document number: DS37672 Rev. 5 - 2
1 of 11
www.diodes.com
July 2015
© Diodes Incorporated