Custom PCB for Wi-i.MX53

Question

I am working on a project where I am designing a custom PCB for the Wi-i.MX53 module, and am having issues getting the module to boot. I have so far copied the boot selection logic circuit, and the power on circuit. But when the board boots nothing happens on the UART0(Console) pins, I have broken these out to a pin header for ttl access. I can see that the power draw increases when I press the power button on my board, so I assume this part works. I have also put a connector for the parallel display interface, but this yields no results either. The module boots fine in a Jumpstart kit board, with output on both the console UART and the display interface.. is there any tricks or appnotes regarding this?

Answer 1

can you check if 3.3v is generated on the module?
Here iss a typical scenario for the power-up sequence of ccwimx53. Highlighted is what gets 3.3v generated.
- Power On power supply
o VCHRG generated on the board. This is the main supply for the CCWMX53 module.
- The PMIC generates the module supplies.
o The +2.775V supply is generated at this point
- The CPU is powered and it check the bootstrap to start boot process
- UBoot sets the PWR_EN signal to enable the external regulators
o The +3.3V supply is generated at this point
- The +3.3V and +5V regulators are enabled and the base board is powered