LM5050-1: Pull up resistor at OFF pin

K.Hamamoto

Guru 12155 points

Part Number: LM5050-1

We are going to calculate the pull up resistor at OFF pin. The pull down current is defined as below,

How much is the pull up resistor calculated at pull up supply voltage = 25V~50V?

The pull down resistor will be calculated as below.

4.5V/3uA=1.5Mohm

4.5V/7uA=643kohm

Is my understanding correct?

Regards,

Koji Hamamot

over 6 years ago

0 Karikalan Selvaraj over 6 years ago

TI__Genius 16305 points

Hi
I am looking into this question, will get back by tomorrow.

Regards,
Kari.

0 K.Hamamoto over 6 years ago in reply to Karikalan Selvaraj

Guru 12155 points

Hi Kari-san,

Thank you for your reply.
Do you have any update for this?

Regards,
Koji Hamamoto

0 Karikalan Selvaraj over 6 years ago in reply to K.Hamamoto

TI__Genius 16305 points

Hi

I am trying to get hold of an EVM to verify this.

Regards,
Kari.

0 K.Hamamoto over 6 years ago in reply to Karikalan Selvaraj

Guru 12155 points

Hi Karikalan,

Do you have any update ?

Regards,
Koji Hamamoto

0 Karikalan Selvaraj over 6 years ago in reply to K.Hamamoto

TI__Genius 16305 points

Hi Koji,

I have got hold of the EVM and tested the leakage.

The pull down resistor calculation is correct.
4.5V/3uA=1.5Mohm and 4.5V/7uA=643kohm

Regards,
Kari.

0 K.Hamamoto over 6 years ago in reply to Karikalan Selvaraj

Guru 12155 points

Hi Karikalan,

Thank you for the confirmation.

Regards,
Koji Hamamoto

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LM5050-1: Pull up resistor at OFF pin