Voltage Stability Issue between FS6523 SBC and MC33665A TPL Transceiver VDDIO Connection

Jamie-Chen — Wed, 13 Nov 2024 10:32:17 GMT

I am working on a circuit board design that includes an FS6523 SBC and an MC33665A TPL Transceiver. Currently, the SBC's VCCA output is set to 3.3V and is directly connected to the TPL Transceiver's VDDIO.

However, I am observing an issue where the VCCA output voltage increases to around 3.38V - 3.46V when the TPL Transceiver is connected. When the TPL is removed from the circuit, the voltage stabilizes back at 3.3V.

I would like to ask if it is acceptable for the SBC’s LDO to be directly connected to the VDDIO of the MC33665A TPL Transceiver, or if this could be causing the observed voltage increase.

Additionally, I noticed in the HVBMS RD-K358BMU reference design that two 22-ohm resistors are placed in series with the 3.3V LDO output from the SBC. Could these resistors be included to prevent voltage rise?

Thank you for your assistance.

Re: Voltage Stability Issue between FS6523 SBC and MC33665A TPL Transceiver VDDIO Connection

TomasVaverka — Wed, 13 Nov 2024 11:58:58 GMT

Hi Ivan (@ivanlovas), Amélie (@AmMeyer),

Could one of you please help with request from XING Mobility Taiwan?

Thanks & BRs, Tomas

topic Re: Voltage Stability Issue between FS6523 SBC and MC33665A TPL Transceiver VDDIO Connection in Power Management

Voltage Stability Issue between FS6523 SBC and MC33665A TPL Transceiver VDDIO Connection

Re: Voltage Stability Issue between FS6523 SBC and MC33665A TPL Transceiver VDDIO Connection