LM7480: schematic check

GARETH OU

Guru 11585 points

Part Number: LM7480

Could you help the check below LM7480 schematic and any need to adjust ,Thanks

LM7480 and TPS552892.pdf

over 1 year ago

0 Shiven Dhir over 1 year ago

TI__Guru 51715 points

Hi Gareth,

The schematic looks fine. Although Input TVS are missing which are essential to pass ISO pulse 1.

Regards,

Shiven Dhir

0 GARETH OU over 1 year ago in reply to Shiven Dhir

Guru 11585 points

Hi Shiven

May I ask why DEMO BRD needs to add D6?

0 Shiven Dhir over 1 year ago in reply to GARETH OU

TI__Guru 51715 points

Hi Gareth,

The purpose of D2 is to supply voltage to the VS pin from A pin. The 10 kohms in series with VS pin (which is placed to limit the current into Zener) limits the current required by the charge pump during startup conditions. So, a diode from A to VS provides uninterrupted current into the VS pin.

Regards,

Shiven Dhir

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LM7480: schematic check