LMZ31520: INH pin always Low

Mani Selvam Palanivel

Part Number: LMZ31520

Hi,

LMZ31520RLGT is used in one of our project for generating the 1.5V supply . When powered ON the board, This IC is not giving the output . In further analysis we found INH pin is low. This INH pin driven by CPLD through one MOSFET as like Figure 20 in datasheet.

Please give your suggestion Why INH pin is in Low always?

over 4 years ago

0 Jimmy Hua over 4 years ago

TI__Mastermind 47060 points

Hi Mani,

How many of your boards have this INH pin pulled low issue? If you replace the existing device with a new device does the failure mode still occur? Could you provide the schematic and PCB layout for review?

The INH pin has an internal pull up current source to allow users the ability to float the INH pin for enabling the device.

Regards,

Jimmy

0 Mani Selvam Palanivel over 4 years ago in reply to Jimmy Hua

Intellectual 360 points

Hi Jimmy,

I appreciate for your immediate response.

Found INH pin had short with GND pin. Now It start to work fine after removed the short.

Thanks.

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LMZ31520: INH pin always Low