Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

LED Driver Circuit with flyback transformer

Status
Not open for further replies.

Kekkaishi

Member level 1
Joined
Jun 25, 2008
Messages
38
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,286
Activity points
1,581
Hello to everyone,

Currently I'm designing LED drvr cct. The specs for my design are as follow:

*********************************
Vin = 100 - 240 V
Vo = 20
Po = 100
efficiency = 80%
duty cycle = 0.45
flyback transformer, isolated and DCM
using TL5001 and optocoupler
*********************************

Attached is my circuit for the design. I need guidance from the expert or anyone on how to implement the PWM using TL5001 with opto-coupler. Is this design okay? Is the value of capacitors and resistors correct? I designing the TL5001 based on the example application using TL5001 but the example only for step down converter and low voltage. I also need someone to check my feedback design.

Sorry for my bad English.

Thank you for all your help.
 

Kekkaishi

Member level 1
Joined
Jun 25, 2008
Messages
38
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,286
Activity points
1,581
Re: LED Flyback Circuit

anyone? please guide me.... Just need someone to check my schematic, the value of the feedback and PWM design.
 

Kekkaishi

Member level 1
Joined
Jun 25, 2008
Messages
38
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,286
Activity points
1,581
LED Flyback Circuit

Anybody, need help at least could anybody tell me whether the connection of my optocoupler is correct or not? should I connect it to the Feedback of TL5001 or VCC. I've searched the forum but still confused.
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
46,988
Helped
13,938
Reputation
28,124
Reaction score
12,576
Trophy points
1,393
Location
Bochum, Germany
Activity points
273,976
LED Flyback Circuit

You should analyze the circuit rather than searching the forum. No current will flow through the optocoupler in the presented circuit.
 

Kekkaishi

Member level 1
Joined
Jun 25, 2008
Messages
38
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,286
Activity points
1,581
LED Flyback Circuit

I'll try to analyze the circuit by referring to AN4137. I really confused on this thing and need some guide. I still learning about power electronic. Could you please help me?

In the AN4137 example, it connected the opto-coupler at two point. I want to let the variable resistor to control the current and that's why I connect it at the cathode of the led. May I know where is the correct location to connect the opto-coupler.

One more thing, in the example of TL5001 the feedback pin connects to two parallel resistor. Do I need these resistors?
 

    V

    points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top