RT7306GS

RT7306 Primary-Side Regulation Dimmable LED Driver Controller with Active-PFC General Description Features The RT7306 is a constant current LED driver with active Tight LED Current Regulation power factor correction. It supports high power factor No Opto-Coupler and TL431 Required across a wide range of line voltages, and it drives the Power Factor Correction (PFC) converter in the Quasi-Resonant (QR) mode to achieve Compatible with Analog Dimming higher efficiency. By using Primary Side Regulation Built-in HV Start-up Device (PSR), the RT7306 controls the output current Quasi-Resonant accurately without a shunt regulator and an opto-coupler Maximum/Minimum Switching Frequency at the secondary side, reducing the external component Clamping count, the cost, and the volume of the driver board. Maximum/Minimum on-Time Limitation Wide VDD Range (up to 34V) RT7306 is compatible with analog dimming. The output THD Optimization current can be modulated by the DIM pin. An in-house Input-Voltage Feed-Forward Compensation design high voltage (HV) start-up device is integrated in Multiple Protection Features the RT7306 to minimize the power loss and shorten the LED Open-Circuit Protection start-up time. LED Short-Circuit Protection The RT7306 embeds comprehensive protection Output Diode Short-Circuit Protection functions for robust designs, including LED open-circuit VDD Under-Voltage Lockout protection, LED short-circuit protection, output diode VDD Over-Voltage Protection short-circuit protection, VDD Under-Voltage Lockout Over-Temperature Protection (UVLO), VDD Over-Voltage Protection (VDD OVP), Cycle-by-Cycle Current Limitation Over-Temperature Protection (OTP), and cycle-by-cycle current limitation. Applications AC/DC LED Lighting Driver Simplified Application Circuit Buck-Boost Application Circuit Flyback Application Circuit TX1 BD D OUT V BD TX1 OUT- V OUT+ Line R Line HV C RHV IN COUT C C OUT IN D HV OUT V HV OUT- Neutral VDD V OUT+ VDD Neutral Q1 C RT7306 VDD GD Q1 GD C VDD RT7306 COMP R PC COMP CCOMP CS R PC R CS C CS COMP Analog DIM R CS Dimming Analog GND DIM ZCD Signal Dimming ZCD GND D AUX Signal D AUX R ZCD1 R ZCD1 R ZCD2 R ZCD2 Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS7306-02 January 2016 www.richtek.com 1 RT7306 Ordering Information Marking Information RT7306GS : Product Number RT7306 RT7306 YMDNN : Date Code Package Type GSYMDNN S : SOP-8 Lead Plating System G : Green (Halogen Free and Pb Free) Pin Configurations (TOP VIEW) Note : Richtek products are : 8 HV VDD 2 7 GND GD RoHS compliant and compatible with the current 3 6 COMP CS requirements of IPC/JEDEC J-STD-020. 4 DIM 5 ZCD Suitable for use in SnPb or Pb-free soldering processes. SOP-8 Functional Pin Description Pin No. Pin Name Pin Function 1 HV High Voltage Input for Startup. 2 GND Ground of the Controller. 3 COMP Compensation Node. Output of the internal trans-conductance amplifier. Analog Dimming Signal Input. LED driving current can be adjusted by an analog 4 DIM voltage. Zero Current Detection Input. This pin is used to sense the voltage at auxiliary winding 5 ZCD of the transformer. 6 CS Current Sense Input. Connect this pin to the current sense resistor. 7 GD Gate Driver Output for External Power MOSFET. Supply Voltage (V ) Input. The controller will be enabled when V exceeds V DD DD TH ON 8 VDD and disabled when V is lower than V . DD TH OFF Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS7306-02 January 2016 2