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FL7730 — Single-Stage Primary-Side-Regulation PWM Controller for PFC and LED Dimmable Driving
FL7730 Single-Stage Primary-Side-Regulation PWM Controller for PFC and LED Dimmable Driving
Features
Compatible with Traditional TRIAC Control
(No need to change existing lamp infrastructure: wall switch & wire)
Compatible with Non-Dimming Lamp Designs Cost-Effective Solution without Input Bulk Capacitor
and Feedback Circuitry
Power Factor Correction (PFC) Accurate Constant-Current (CC) Control,
Independent Online Voltage, Output Voltage, Magnetizing Inductance Variation
Line Voltage Compensation for CC Control Linear Frequency Control for Better Efficiency and
Simple Design
Open-LED Protection Short-LED Protection Cycle-by-Cycle Current Limiting Over-Temperature Protection with Auto Restart Low Startup Current: 20 μA Low Operating Current: 5 mA SOP-8 Package Available Application Voltage Range: 80 VAC ~ 308 VAC
Applications
LED Lighting System
Description
This highly integrated PWM controller, FL7730, provides several features to enhance the performance of singlestage flyback converters. The proprietary topology, TRUECURRENT® enables the simplified circuit design for LED lighting applications.
TRIAC dimming is smoothly managed by dimming brightness control without flicker. By using single-stage topology with primary-side regulation, an LED lighting board can be implemented with few external components and minimized cost. It does not require an input bulk capacitor or feedback circuitry. To implement good power factor and low total harmonic distortion, constant on-time control is utilized with an external capacitor connected to the COMI pin.
Precise constant-current control regulates accurate output current versus changes in input voltage and output voltage. The operating frequency is proportionally changed by the output voltage to guarantee Discontinuous Conduction Mode (DCM) operation with higher efficiency and simpler design. The FL7730 provides protections such as open-LED, short-LED, and over-temperature protections. Current-limit level is automatically reduced to minimize output current and protect external components in a short-LED condition.
The FL7730 controller is available in an 8-pin Small Outline Package (SOP).
Related Resources
Evaluation Board: FEBFL7730_L20L008A
Evaluation Board: FEBFL7730_L20H008A
Ordering Information
Part Number Operating Temperature Range
Package
FL7730MY_F116
-40°C to +125°C
8-Lead, Small Outline Package (SOP-8)
Packing Method
Tape & Reel
© 2011 Fairchild Semiconductor Corporation FL7730 • Rev. 2, Feb-2020
www.fairchildsemi.com
FL7730 — Single-Stage Primary-Side-Regulation PWM Controller for PFC and LED Dimmable Driving
Application Diagram
Internal Block Diagram
Figure 1. Typical Application
© 2011 Fairchild Semiconductor Corporation FL7730 • Rev. 2, Feb-2020
Figure 2. Functional Block Diagram
2
www.fairchildsemi.com
FL7730 — Single-Stage Primary-Side-Regulation PWM .