topic eMMC CLK Voltage in i.MX Processors

eMMC CLK Voltage

coilnpark — Tue, 06 Jul 2021 08:05:38 GMT

Hi all,

I am developping custom board by using SABRESD board.

I have a simpmle question.

As I know, emmc CLK voltage is proper 3.3V or 1.8V according to the VCC or VCCQ voltage.

However, my board CLK voltage is 5V as below the picture.

When I checked SD card CLK, it was also 5V.

I am using usdhc2, 4 (eMMC is using usdhc4)

Anybody can help me?

igorpadykov — Tue, 06 Jul 2021 11:47:47 GMT

Hi Coiln

from i.MX6Q side voltage should be as described in Table 96. 21 x 21 mm Functional Contact Assignments, column "Power Group"

If it is 5V, probably it is shorted to some other signal.

Best regards
igor

coilnpark — Tue, 06 Jul 2021 12:12:18 GMT

Hi igor

Thank you for your prompt reply.

I also tested sdcard clk of SABRESD kit.

The sdcard clk voltage was 4.3V

Even I will check our board for high voltage, SABRESD kit voltage is also weird.

Could you check it?

Best regards,

Colin Park

coilnpark — Wed, 07 Jul 2021 06:19:56 GMT

Hi, igor

I refered the scehmetic of SABRESD NXP_SPF-27392_C3. It used just GEN3V3.

Do I have to use "NVCC_NANDF" Power?

[SPF-27392_C3]

[My board]