Vsense in MC33FS4503

[jingfang]

Data sheet: Vsense must be connected to the battery line(before the reverse battery protection diode),but the PCB is recommends to be connected behind the diode.

We originally designed Power A,but now we want to add Power B. We want to move the node to the positon of the red arrow. Will this have any impact?

[TomasVaverka · Accepted solution]

Hello Jingfang,

Both connections are OK from a functional safety point of view since VSENSE is rated -14 to 40V (with ext R in series mandatory) and is also the redundant supply for the Fail-safe machine (primary supply is VSUP3).

Having said that, we recommend to connect the VSENSE pin before the reverse protection diode. This allows to have the real image of the battery voltage for the sensing (for the AMUX for instance), avoiding the drop in the diode.

Best regards,

Tomas