TPS61022: SW pin shorted to GND

Louis Han15

Genius 4680 points

Part Number: TPS61022

Hello

The SW pin was shorted to GND while testing the Supercapacitor backup power supply with the TPS61022 at the customer.

I have attached the circuit diagram and waveform, so please check it.

Yello : VOUT

Red : Vin

Best regards.

over 3 years ago

0 Zack Liu over 3 years ago

TI__Mastermind 34231 points

Hi Louis,

For TPS61022 working in Supercap backup power supply application, please follow the app note to re-design the schematic. The reason is at low Vin condition, the device needs to be carefully compensated, otherwise the loop is unstable.

Could you also share the layout, the failure issue is highly possible related to layout. Thanks.

0 Louis Han15 over 3 years ago in reply to Zack Liu

Genius 4680 points

Hi Zack

Thanks for your support.

I attached layout data.

please check the layout.

7357.layout.pdf

Best regards.

0 Zack Liu over 3 years ago in reply to Louis Han15

TI__Mastermind 34231 points

Hi Louis,

Please see below suggestions on TPS61022 circuit layout:

The output capacitor position is more important for TPS61022 boost converter layout. Place this ceramic capacitor close to IC Vout pin and GND pin.

I did see similar failure case with similar layout like yours.

Please read the TPS61022 layout guideline app note for more details.

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TPS61022: SW pin shorted to GND