• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 62 subscribers
  • Views 197 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TPS92640: TPS92640 "Rcs" component thermal issue

harold
Prodigy 10 points
Part Number: TPS92640

Tool/software:

Hello

I am using TPS92640 IC and using analog dimming with IADJ terminal. (There is no PWM signal on UDIM terminal)

However, when operating with output current of 3A, Rcs(Sensing Resister) part temperature rises to over 130 degrees.

Other parts are around 50~80 degrees.

Please tell me how to lower the temperature of Rcs part.

[ Circuit ]

1. Rcs value: 0.08ohm x 1ea  (2512 size, 2W)

2. VIN : 24V

3. VLED Output voltage : about 21V

4. Output current : below 3A

5. L : 10uH

6. Cout: 100uF/50V

7. PCB : 1.6T, FR-4, 2-Layer

Best regards,

harold.

  • 0
    TI__Mastermind 27286 points

    Hi Harold

    Maybe you can decrease the IADJ and RCS value proportionally to realize the target I_LED .

    Can you please share the waveform of the SW voltage and the RCS? And can you please share the layout image?

    Thanks and best regards.

  • 0
    TI__Mastermind 27286 points

    Hi Harold

    Is there any update? The thermal dissipation on RCS is ~Irms^2*RCS , you can adjust the VIADJ so that you can select smaller RCS value. 

    I will close this thread if there is no other questions.

    Thanks and best regards.