RT7306 Datasheet, PDF (1/17 Pages) Richtek Technology Corporation – The RT7306 is a constant current LED driver

RT7306
Primary-Side Regulation Dimmable LED Driver Controller
with Active-PFC
General Description
The RT7306 is a constant current LED driver with active
power factor correction. 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), the RT7306 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.
RT7306 is compatible with analog dimming. The output
current can be modulated by the DIM pin. An in-house
design high voltage (HV) start-up device is integrated in
the RT7306 to minimize the power loss and shorten the
start-up time.
The RT7306 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 (VDD OVP),
Over-Temperature Protection (OTP), and cycle-by-cycle
current limitation.
Features
 Tight LED Current Regulation
 No Opto-Coupler and TL431 Required
 Power Factor Correction (PFC)
 Compatible with Analog Dimming
 Built-in HV Start-up Device
 Quasi-Resonant
 Maximum/Minimum Switching Frequency
Clamping
 Maximum/Minimum on-Time Limitation
 Wide VDD Range (up to 34V)
 THD Optimization
 Input-Voltage Feed-Forward Compensation
 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
Applications
 AC/DC LED Lighting Driver
Simplified Application Circuit
Flyback Application Circuit
Buck-Boost Application Circuit
Line
Neutral
BD
CIN
RHV
VDD ^HV
CVDD
GD
RT7306
TX1 ^DOUT
Q1
VOUT+
COUT
VOUT-
Line
Neutral
COMP
CCOMP
RPC
CS
Analog
DIM
RCS
Dimming
ZCD
GND
Signal
DAUX
RZCD1
RZCD2
BD
CIN
RHV
HV
VDD
CVDD
RT7306 _GD
TX1
DOUT
Q1
VOUT-
COUT
VOUT+
COMP
CCOMP
CS
Analog
Dimming
Signal
DIM
ZCD
GND
DAUX
RPC
RCS
RZCD1
RZCD2
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS7306-00 July 2015
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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