Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics 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

Sg3525 feedback problem

Status
Not open for further replies.
H

hamid159

Full Member level 3
Joined
Aug 25, 2013
Messages
176
Helped
14
Reputation
28
Reaction score
14
Trophy points
1,298
Location
Lahore
Activity points
2,488
Hi guyz,
i'm having problem related to sg3525 feedback.i've made a circuit but don't know how i can implement the feedback circuit.please help me.output voltage is about 24V.
 

Attachments

  • UC2525IC.PDF
    40.4 KB · Views: 184

You have made a Half bridge circuit.
Please try this link for feed back circuit design, It is for push pull converter but logic is same.You have to redesign the voltage divider.
**broken link removed**
 

Thanks smijesh,
what is the purpose of resistors and capacitors at pin 1 of sg3525.how it works.i've used this type of feedback but except resistors and capacitors at pin 1.but output voltages is not regulated.At 5amperes load,output voltage drops by 2.5V and at 8 amperes,it drops by 4.7V.is this a normal case or I can make it better by proper feedback?Please help me guyzz.here is schematic
 

Attachments

  • sg3525 tl431 feedback.pdf
    58.3 KB · Views: 236

The theory behind the feed back : A voltage comparator having inverting terminal and non inverting terminal. You have to set a reference voltage to non inverting terminal say 2.6V (5.5 Reff of sg2525 / 2). Then you give 2.6V to inverting terminal from output through opto isolator. If any change from output will change the PWM duty cycle of PWM. Capacitor is using for filtering the spike in the voltage.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top