S12ZVML EXTERNAL BALLAST PNP FOR CAN PHYSICAL SUPPLY

[matteo_baldina]

Hello to everybody,

For my project I want to use the MCU S912ZVML31F1WKF. It has a LIN physical layer, the MSCAN module and 48 pin package, I chose it for this reason beacause I have a really small PCB area and I don't need many I/Os pin.

I saw in the reference manual there is the possibility to connect an external PNP transistor for the supply an higher current without the risk of overtemperature of the internal LDO of MCU.

Q1: Can I supply an external CAN physical layer with the pin VDDx and the external PNP or there are some issues?

Q2: If it is not possible to use VDDx and PNP for this purpose, will it be necessary to switch on 64 pin package with VDDC pin?

Thanks for the attention,

MB

[lama]

Hi,

I am very sorry, I am not allowed to claim anything which is not in conformity with our design team announcement. It is not recommended to use this supply configuration for another purpose. If you use it in this way all tests and responsibility is up to you.
Theoretically it can work (ibctl is max 2.3mA) but nobody from design team recommends it and nobody has tested this behavior because the design was not done for this purpose. You have to consider your all consumption of loads connected to Vddx and all possible inputs (characteristics of connected devices) if you want to test this design.
However, and again, if you use this configuration all tests,  quality, risks and responsibility will be up to you.

Best regards,

Ladislav