MPC5746R VDD_HV_IO_JTAG

[jinjingyang]

Dear Sir,

According to datasheet, VDD_HV_IO_JTAG need be 3.3V if using JTAG features of those pins on MCU.

In my application, only 1.25V and 5.0V are supplied.

Can I use 5V to supply VDD_HV_IO_JTAG?

I checked with 5V applied on VDD_HV_IO_JTAG. MCU is running OK and Lauterbach debugger communication to MCU JTAG is also OK.

Is there any problem or risk of using 5V on VDD_HV_IO_JTAG?

Jason Yang

[lukaszadrapa]

Hi Jason,

this is copied from Hardware design guide AN4998 - footnote below Figure 1:

"VDD_HV_IO_JTAG is typically powered by a 3.3 V supply for compatibility with many debug tools. However if tools support 5 V or JTAG access is not required, a 5 V supply may be used and the JTAG pins can be used as normal GPIO."

Regards,

Lukas

[petervlna]

Hi,

Yes you can run VDD_HV_IO_JTAG as datasheet describes.

Peter