Hi NXP technician,
This is Ted from Melecs Wuxi, nice to contact you.
I have one question about the structure of S32M276 IC. ( pls. refer to the attached file: Schematic- S32M276).
I did the design as datasheet recommendation, connect the 9pin-VDD_AE10, 12pin,25pin,37pin-VDD_HV_A together with beads. from my understanding, 9pin-VDD_AE10 P5V output voltage is generated by internal regulator, then supply the MCU-die on VDD_HV_A pin.
But I removed L300, and after that, the PCBA could still working as normal.
So my question is that the VDD_AE10 pin and VDD_HV_A pin are internally connected together? Otherwise, after removing L300 system still work, which does not make sense..
Hi Ted,
When L300 is removed, what voltage do you measure on VDD_HV_A?
The MCU-side power supply domain VDD_HV_A is likely powered through the GPIOs that are shared between the MCU and the AE side, because all GPIOs are clamped to VDD_HV_A. In other words, VDD_HV_A can be powered through any pin if the voltage on that pin is greater than VDD_HV_A. You should therefore measure approximately VDD_HV_A = VDD_AE10 - Vf, not VDD_HV_A = VDD_AE10.
Thank you,
BR, Daniel
Hi Daniel,
Thanks for your reply.
1, So it means that the VDD_AE10 and VDD_HV_A are internally connected?
And I could not understand the meaning of this sentence
[And you should measure VDD_AE10 - Vf on VDD_HV_A - this can damage the device.]
If you could give me some more explanation.
Hi Ted,
The AE die generates VDD_AE10.
On the AE side, VDD_AE10 is the power supply of the AE ports, all the ports are clamped to VDD_AE10.
On the MCU side, VDD_HV_A is the power supply of the MCU ports, all the ports are clamped to VDD_HV_A.
These two dies are interconnected.
If the input voltage on any MCU port is higher than VDD_HV_A + Vf of the clamp, the VDD_HV_A domain is going to be powered by the injected current. And you should measure VDD_AE10 - Vf on VDD_HV_A - this can damage the device.
Regards,
Daniel