Primary feedback flyback LED constant current driver based on power tube drain detection technology

A technology of constant current driver and detection technology, which is applied in the direction of light sources, electrical components, lighting devices, etc., and can solve problems such as large temperature fluctuations, gradual attenuation of conversion efficiency, and increase in the number of peripheral devices

Inactive Publication Date: 2019-02-22
HUAZHONG UNIV OF SCI & TECH +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The secondary side feedback uses the optocoupler element to sample and feedback the secondary side information. This feedback mode can accurately control the output signal, but the optocoupler device increases the number of peripheral devices, and has disadvantages such as easy aging, large temperature drift, and gradual attenuation of conversion efficiency.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Primary feedback flyback LED constant current driver based on power tube drain detection technology
  • Primary feedback flyback LED constant current driver based on power tube drain detection technology
  • Primary feedback flyback LED constant current driver based on power tube drain detection technology

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] The present invention will be further described below in conjunction with accompanying drawing:

[0023] Such as figure 1 Shown: the present invention is made up of EMI filter, rectifier, three capacitors, two resistors, transformer, thyristor, diode, light-emitting diode, drive and PWM controller.

[0024] The drive includes a secondary conduction time module and an LED output current estimation module. The LED output current estimation module is composed of LEB, a dual operational amplifier chip, three capacitors, two resistors and three switches.

[0025] The secondary conduction time module is composed of a capacitor, two resistors, a switch, an operational amplifier chip and a time relay.

[0026] The LEB is composed of four operational amplifier chips and a capacitor.

[0027] The primary side feedback flyback LED constant current driver system based on power tube drain detection technology is as follows: figure 2 As shown, the system mainly includes EMI filte...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a primary side feedback flyback LED constant current driver based on power tube drain detection technology, which consists of an EMI filter, a rectifier, a large capacitor Cin, an RCD absorption circuit, a flyback transformer, a power MOS tube, a primary side It consists of sampling resistor Rcs, secondary diode D0, output capacitor Co, LED, secondary on-time acquisition module, LED output current estimation module and PWM controller. Compared with the prior art, the present invention does not need an optocoupler device and an auxiliary winding, and obtains the conduction time information of the secondary diode by detecting the drain of the power switch tube, and the peak current information of the primary side obtained by sampling the source of the power MOSFET, and inputs them together To the PWM controller, the PWM controller obtains the output current information through calculation, so as to control the LED output current to be constant.

Description

technical field [0001] The invention relates to an LED constant current driving circuit, in particular to a primary side feedback flyback LED constant current driver based on power tube drain detection technology. Background technique [0002] LED has the characteristics of high brightness, long life, stable brightness and environmental protection, and has been widely used. The flyback topology has the advantages of low cost and simple structure, and is widely used in driving small and medium power LEDs. Based on the flyback topology LED constant current drive design, there are two main feedback methods: secondary side feedback and primary side feedback. The secondary side feedback uses the optocoupler element to sample and feedback the secondary side information. This feedback mode can accurately control the output signal, but the optocoupler device increases the number of peripheral devices, and has disadvantages such as easy aging, large temperature drift, and gradual at...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H05B33/08H05B44/00
CPCH05B45/37
Inventor 陈晓飞资海平董一帆郑朝霞邹雪城
Owner HUAZHONG UNIV OF SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap