4GB LPDDR4 failed calibration on iMX8M Plus

[Zhirong_Yang]

Hi NXP Team,

  Our iMX8M Plus Quad Core based board was previously load with 2GB LPDDR4 (MT53E512M32D1ZW-046) and has been working normally, but recently we build a batch of 4GB LPDDR4 (MT53E1G32D2FW-046) board, and it failed DDR calibration ' Step 2' as show in below.

============ Step 2: DDR memory accessing... ============
Verifying DDR frequency [email protected] of failure: 0x0000000040080000
Data read was:   0x4007FFE000000000
But pattern was: 0x0000000040000000
Failed
Please modify DDRC/DFI parameters!!!

Please someone can help how to fix this issue?

[JorgeCas]

Hello,

You could try to change the tunning with different settings and check if helps with your design:

ODTImpedance

Desired ODT impedance in Ohm. Valid values for DDR4=240,120,80,60,40. Valid values for DDR3L=high-impedance,120,60,40. Valid values for LPDDR4=240,120,80,60,40

TxImpedance

Write Driver Impedance for DQ/DQS in ohm (Valid values for all DDR type= 240, 120, 80, 60, 48, 40, 34)

ATxImpedance

Write Driver Impedance for Address/Command (AC) bus in ohm (Valid values for all DDR type = 120, 60, 40, 30, 24, 20)

Best regards.

[Zhirong_Yang]

@JorgeCas ,

  We tried different ATx, ODT, Tx Impedance combinations and no improvement.

Is there any other way?

[JorgeCas]

Hello,

If you still have this issue, the root cause could be layout issues since electrical characteristics between each memory could vary.

Please confirm that you are using the correct settings for the new memory.

Also, please try to use the latest tool version.

Best regards.