/a>LED” title=”LED”>LED” title=”LED”>LED lighting application circuit design, thereby reducing costs, improving power factor, and reducing total harmonic distortion. Starting current 20uA, working current 5mA, main In LED lighting. This article introduces the main characteristics of FL7730MY, block diagram, input voltage 90-140VAC TRIAC dimming LED driver circuit diagram and 90V-264VAC evaluation board 5.0V/0.7A mobile phone battery charger main indicators, circuit diagram, bill of materials and PCB Layout.
FL7730MY:Single-Stage Primary-Side-Regulation PWM Controller for PFC and LED Dimmable Driving
This highly integrated PWM controller, FL7730MY, provides several features to enhance the performance of single-stage 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 FL7730MY 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 FL7730MY frequency-hopping function in the oscillator improves EMI performance. The FL7730MY controller is available in an 8-pin SOP package.
Main features of FL7730MY:
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
Cycle-by-Cycle Current Limiting
Over-Temperature Protection with Auto Restart
Low Startup Current: 20μA
Low Operating Current: 5mA
Frequency Hopping for Better EMI Performance
SOP-8 Package Available
LED Lighting System
Figure 1. Block diagram of FL7730MY
Figure 2. FL7730MY TRIAC dimming LED driver circuit diagram (input voltage 90-140VAC)
FEBFSEZ1317A_CH310v3 evaluation board 5.0V/0.7A mobile phone battery charger
This document describes a 3.5W power supply using an FSEZ1317AMY device. This power supply is targeted for mobile phone battery chargers for a 30mW solution with high efficiency.
The controller used on the board is Fairchild semiconductor‘s FSEZ1317AMY. This third-generation Primary-Side-Regulation (PSR) PWM controller with integrated MOSFET and improved EMI performance provides several features to enhance the performance of low-power flyback converters. The proprietary TRUECURRENT® technology enables precise Constant Current (CC) regulation and simplified circuit design for battery-charger applications. The result is a lower-cost, smaller, and lighter charger compared to conventional designs or a linear transformer. To minimize standby power consumption (30mW at 265VAC ), a proprietary Green Mode provides off-time modulation to linearly decrease PWM frequency under light-load conditions. Green Mode assists the power supply in meeting power conservation requirements. By using the FSEZ1317A, a charger can be implemented with few external components and minimized cost.
Main indicators of 5.0V/0.7A mobile phone battery charger:
Figure 4. 5.0V/0.7A mobile phone battery charger outline drawing
Figure 5. 5.0V/0.7A mobile phone battery charger circuit diagram
5.0V/0.7A mobile phone battery charger material list:
Figure 6. 5.0V/0.7A mobile phone battery charger PCB layout: top: top layer, middle: middle layer, bottom: bottom layer,
For details, see: