Unable to program MCXN236VNLT custom board

[sstcor]

Designed a PCB based on the MCXN236VNLT and am trying to program the board using an MCU-Link debug probe, but I am getting the following error.

LinkFlash tool output

[Alice_Yang · Accepted solution]

Hello @sstcor 

Please review the ​FRDM-MCXN236 board schematic and verify your hardware design, particularly the ​SWD interface and ​power circuitry.

https://www.nxp.com/design/design-center/development-boards-and-designs/FRDM-MCXN236  

BR

Alice

[sstcor]

Hi @Alice_Yang ,

After reviewing the schematic, I noticed VDD_SYS on the board is outputting ~3.2V and the datasheet says it should be between 1.71-1.98 V. It's floating in the schematic. Is it normal on 100 pin package?

I have connected the following pins to MCU-Link.

MCU-Link	NXP MCXN236
VTarget	3.3V
GND	GND
SWDIO	SWDIO
SWCLK	SWCLK
RESET	RESET

Multimeter readings: VDD_MCU = 3.3 V, VCore = 1 V

[sstcor]

Issue resolved. Missing a 2.2uF capacitor on VDD_SYS pin.