TPS61280A: Device does not start to work

Yehuda Mark

Prodigy 175 points

Part Number: TPS61280A

The circuit is implemented exactly like TPS61280EVM Schematic except that EN, nByp and Vsel are connected to Vin,

It will not start to work through all the input voltage range

Tests done with load, small load and no load at all, results are the same

Any suggestions why the TPS61280A does not start to work

Thanks,

Yehuda Mark

over 4 years ago

0 Jasper Li over 4 years ago

TI__Mastermind 46905 points

Hi Yehuda,

could you help to measure the input voltage at the same image?

0 Yehuda Mark over 4 years ago in reply to Jasper Li

Prodigy 175 points

Hi Jasper,

The power supply is a Lab power supply, dual output set to work in parallel to allow 4A consumption, made by Horizon

attached are the scope screen shots of the input voltage vs output voltage

note that the GPIO pin is not connected, could this the source of the problem

Best Regards,

Yehuda

0 Yehuda Mark over 4 years ago in reply to Jasper Li

Prodigy 175 points

Hi Jasper,

The power supply is a Lab power supply, dual output set to work in parallel to allow 4A consumption, made by Horizon

attached are the scope screen shots of the input voltage vs output voltage

The GPIO in my design is left unconnected, can this be the source of the problem

Best Regards,

Yehuda

0 Jasper Li over 4 years ago in reply to Yehuda Mark

TI__Mastermind 46905 points

Hi Yehuda,

yes, the GPIO must be connected to high through 1K~10K resistor.

0 Yehuda Mark over 4 years ago in reply to Jasper Li

Prodigy 175 points

Hi Jasper,

What is the effect if the GPIO is not terminated?

Is there a way to configure it only as output

Best Regards,

Yehuda

0 Jasper Li over 4 years ago in reply to Yehuda Mark

TI__Mastermind 46905 points

Hi Yehuda,

the device will keep restart as you observed.

you can configure the GPIO pin function to MODE pin through I2C.

0 Yehuda Mark over 4 years ago in reply to Jasper Li

Prodigy 175 points

Hi Jasper,

I configured the GPIO to mode through I2C and now it works

On the next HW spin I'll add the pull-up resistor

Thanks very much on the quick and prompt response, it was a great help

Best Regards,

Yehuda

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TPS61280A: Device does not start to work