This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UCC28C53: SMPS

Part Number: UCC28C53
Other Parts Discussed in Thread: UCC28C55, , UCC2800, UCC28C54

Hi 

I have design SMPS using UCC28C55 . I am start designing one solution on below both requirement. I have done schematic and also attached please review and comment.

Input 15-80VDC/80-400VDC

Output- 5V/2A

smps_hv_low_wattage.pdf

I have marked below picture. Please suggest me.

  • The schematic you've shown looks like the right starting point and all the component placeholders appear correct. Not sure why the PWM controller shown in your schematic is UCC2800 but the PWM mentioned in your E2E post is UCC28C53 and UCC28C55? Please finish the schematic and show all component values. You can also use TI Power Stage Designer for designing/verifying your power stage and modelling the compensation. Based on your minimum input voltage of 15V, I believe you should be considering a PWM controller such as UCC28C54.

    Regards,

    Steve M

  • I am using PWM controller  UCC28C53.Alread discussed my previous thread.

    I have some question in attachment snapshot Please suggest me

    1. Rss and Css form an RC delay on COMP for the purpose of soft-start. See UCCx8C5y data sheet, section 8.3.7 for description.
    2. Rramp and Cramp form slope compensation. See UCCx8C5y data sheet, section 8.3.9 for description. You will notice from Figure 8-8 that Cramp is not shown and this is ok. The Cramp is ok to add but if used a resistor is needed, connected between the emitter/Cramp junction and GND. Recommendation is to follow the slope comp, shown in Figure 8-8.

    Regards,

    Steve