RT7310 Datasheet, PDF (1/12 Pages) Richtek Technology Corporation – Phase-Cut Dimmable Primary-Side Regulation

RT7310
Phase-Cut Dimmable Primary-Side Regulation
LED Driver Controller with Active PFC
General Description
The RT7310 is a high power factor constant current
LED driver which is optimized for the compatibility with
phase-cut dimmers. It supports high power factor
across a wide range of line voltages, and it drives the
converter in the Quasi-Resonant (QR) mode to achieve
higher efficiency. By using Primary Side Regulation
(PSR), RT7310 controls the output current accurately
without a shunt regulator and an opto-coupler at the
secondary side, reducing the external component count,
the cost, and the volume of the driver board.
The RT7310 supports phase-cut dimmers, including
leading-edge (TRIAC) and trailing-edge dimmers.
RT7310 embeds comprehensive protection functions for
robust designs, including LED open circuit protection,
LED short circuit protection, output diode short-circuit
protection, VDD Under-Voltage Lockout (UVLO), VDD
Over-Voltage Protection (OVP), Over-Temperature
Protection (OTP), and cycle-by-cycle current limitation.
Features
 Supporting Phase-Cut Dimmers
 Tight LED Current Regulation
 No Opto-Coupler and TL431 Required
 Power Factor Correction (PFC)
 Quasi-Resonant
 Maximum/Minimum Switching Frequency
Clamping
 Maximum/Minimum On-Time Limitation
 Wide VDD Range (up to 25V)
 Multiple Protection Features :
 LED Open-Circuit Protection
 LED Short-Circuit Protection
 Output Diode Short-Circuit Protection
 VDD Under-Voltage Lockout
 VDD Over-Voltage Protection
 Over-Temperature Protection
 Cycle-by-Cycle Current Limitation
Application
 Phase-Cut Dimmable LED luminaries
Simplified Application Circuit
Flyback Converter
Tapped-Inductor Buck-Boost Converter
L1
Line
CX
RDMR1
Neutral
BD
RDMR2
RST1
CDMR
CM
DZ
CVDD
Q2
DST
RT7310
GD
RPC
CS
VDD
COMP
GND
CCOMP
ZCD
DAUX
TX1 ^DOUT
NP
NS
Q1
VOUT+
COUT
VOUT-
RCS
RZCD2
NA
RZCD1
L1
Line
CX
RDMR1
Neutral
BD
RDMR2
RST1
CDMR
CM
DZ
CVDD
Q2
RT7310
DST
VDD
GD
RPC
CS
COMP
GND
CCOMP
ZCD
DAUX
TX1
N2
DOUT
N1
VOUT-
COUT
VOUT+
Q1
RCS
RZCD2
N3
RZCD1
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS7310-00 October 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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