Where can I find the IO pin spec of iMX53?

[JohnHuang]

Hello all,

I am designing my custom iMX53 board, a little problem found that I can not find the IO pin voltage of IMX53.

For example, if I want to make sure the output hi/low voltage of EIM_DX, which PDF should I check?

[TheAdmiral]

That is correct. On the Quick Start board, there was no NANDF used. The pins from the NVCC_NANDF power domain were used as GPIO pins to support 1.8V devices (accelerometer, camera), so that power rail was connected to 1.8V. If you want to use 3.3V NANDF, then connect NVCC_NANDF and NVCC_PATA to 3.3V to a 3.3V supply source.

[JohnHuang]

Thanks, Mark. I get it.

I found the power rail information in Table 7 of IMX53CEC.pdf

In QSB, the NVCC_NANDF is connected to 1.8V. If I want to use a 3.3V NAND flash in my board, I should change the NVCC_NANDF from 1.8V to 3.3V, is it correct?

If I connect data bus of NAND flash to PATA_DATA[8:0], the NVCC_PATA also need to connect to 3.3V.

Best regards,

John Huang

[TheAdmiral]

The IO pin voltage level is determined by the voltage that you supply to that pins power rail. Each pin is assigned to a particular power rail, and that information can be found in the i.MX53 datasheet, section 6 (not reference manual). For example, pin EIM_D16 is assigned to the NVCC_EIM_SEC power rail. But EIM_DA15 is assigned to the NVCC_EIM_MAIN power rail. You are free to choose what voltage you want to supply to these rails at their power pins, provided you stay within the limits of the datasheet.