TINA/Spice/UC2843AQ: DC/DC DCM Flyback converter power stage transfer function

Thank you Mr Davit，you have solved my question perfectly.
However, do TI have an application note about how to design a DCM flyback like--How to Design Flyback Converter With LM3481 Boost
Controller,this one is about CCM.

Hi,

There are many Power Supply Design Seminar papers available that go more in depth with Flyback design: http://www.ti.com/ww/en/power-training/login.shtml?HQS=app-gen-null-PSDResources-vanity-tr-psds-wwe

Type in "flyback" for the keywords for more in-depth search.

Two documents that go into flyback converter design include: 

Under the Hood of Flyback SMPS Designs: http://www.ti.com/lit/slup261

Control Challenges for Low Power AC/DC Converters: http://www.ti.com/lit/slup325

TI also has a power design tool to aid in component selection depending on topology: http://www.ti.com/tool/powerstage-designer

Regards,

Davit 

Hi, thank you for your anser,now i use the simplis&simetrix to simulate the flyback topology wiith UC2843, and i download the spice model in TI,but the model doesnot have the symbol for this model.

can i use this model in simetrix?

Hey there,

Simplis/SIMetrix has a good tutorial on how to install models here:www.simetrix.co.uk/.../000009.html

Follow this tutorial to learn how to use our PSpice Models in Simplis/SIMetrix.

Regards,

  Davit

In the datasheet of UC3842, I can see the application of Error Amplifier.

I have a question:

       How do I calculate the transfer function of the compensation if I design it like this?

              I usually use :

                     i-=i+=0

                     V+=V-=2.5V

       Do the open collector and current source have an influence of the calculation?

 the word has more detail information(simulation.sxsch and calculation equation)

Forward to your apply, thank you.

 

      

 

 

Hello,

I am having trouble opening your word document.

However, there is a detailed section in the datasheet for finding the voltage feedback loop compensation. The section is 9.2.2.10, Voltage Feedback Compensation, on page 25 of the datasheet (www.ti.com/.../uc3842.pdf).

That section includes content about the power stage poles and zeros, slope compensation, open-loop gain, and the compensation loop. In the end, the datasheet has Equation 59, the closed loop compensation gain transfer function.

Best Regards,
Davit