TPS65105: Voltage Drops when LCD is enabled

ABHISHEK VELAGADA

Part Number: TPS65105
Other Parts Discussed in Thread: TPS61165

HI,

We are using LCD AT070TN92 with LDO TPS65105 for driving required power supplies as shown in attachment. As we enable LCD we see voltage drop in all the voltages of TPS65105. please verify the schematics and suggest any changes required.

For back light of LCD we are using TPS61165.

over 6 years ago

0 Ilona over 6 years ago

TI__Expert 8010 points

Hello Abhishek,

Thanks for your request. It looks like your feedforward capacitor is 4.7 µF, this might be the reason. The feedforward capacitor should be in the pF-range, please change this capacitor to be e.g. 6.8 pF. You can add the 4.7µF additional in parallel to the C158.

Best Regards.
ilona

0 Ilona over 6 years ago in reply to Ilona

TI__Expert 8010 points

Hello Abhishek,

Did this resolve the problem?

Thanks for your feedback.
Best Regards.
ilona

0 Ilona over 6 years ago in reply to Ilona

TI__Expert 8010 points

Hello Abhishek,

Let me check on you again. Did you resolve the issue? If my answer solved your question I appreciate your feedback by clicking on 'this resolved my issue'.

Thank you.
Best Regards.
Ilona

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TPS65105: Voltage Drops when LCD is enabled