54L15 USB Issue

[Randall Hung]

TB-M54L15-SCH.pdf

The customer soldered the 54L15 module to the TB-M54L15 board, unplugged the USB, and used the EVB's SWDCLK, SWDIO, 3.3V, and GND connections to perform earase and read operations on the 54L15. However, I then disconnected the EVB's SWDCLK, SWDIO, 3.3V, and GND connections. Then, plugging in a NB's USB power supply, I measured the LDO power supply on the board and found no 3.3V. Upon checking, I realized the 54L15 module's 3.3V was shorted to GND.Why?

[mathiaso]

Hi, Randall.

I'm unsure if I'm able to grasp all the details here.

Upon checking, I realized the 54L15 module's 3.3V was shorted to GND.

Could you please provide some more insight to this short between 3.3V and GND?

The customer soldered the 54L15 module to the TB-M54L15 board

Which specific 54L15 module are they using? Do you have some more information about this board?

Then, plugging in a NB's USB power supply, I measured the LDO power supply on the board and found no 3.3V.

What do you refer to by "NB" here?

Best regards,
Mathias