LMZM23601: LMZM23601 used for +12 and -12V on the same board

siauhwa ong

Part Number: LMZM23601

Hi,

I would like to use LMZM23601 for +12 and -12V on the same board.
In that case what should the PAD pin tied to ?

Thank you

over 5 years ago

0 Jimmy Hua over 5 years ago

TI__Guru 50120 points

Hi Siauhwa,

The thermal pad is internally connected to PIN1(GND) of the power module. For this inverting buck application the PAD should be tied to nVout. This is because the Pin6(Vout) is now considered system ground and PIN1 and thermal PAD are now configured for nVout.

Regards,

Jimmy

0 siauhwa ong over 5 years ago in reply to Jimmy Hua

Expert 1510 points

Hi Jimmy,

Thank you for your answer.

Just want to confirm :

Thank you

0 Jimmy Hua over 5 years ago in reply to siauhwa ong

TI__Guru 50120 points

Hi Siauhwa,

Top schematic (inverting) and bottom schematic ( regular buck) looks correct.

Referenced is the app note for configuring the LMZM23601 for inverting application.

Regards,

Jimmy

0 siauhwa ong over 5 years ago in reply to Jimmy Hua

Expert 1510 points

Thank you for the app note , Jimmy

So, I just need to provide a -12V plane for heat dissipation (connected to pin 1 & 11 ) for inverting.
And GND plane connected to pin 1 & 11 for non inverting +12V.
Could you please confirm ...

Thank you

0 Jimmy Hua over 5 years ago in reply to siauhwa ong

TI__Guru 50120 points

Yes that sounds correct.

Power management

Power management forum

LMZM23601: LMZM23601 used for +12 and -12V on the same board