According to the reference design of I.MX6 SabreSD board, we design our circuit boards. Recently, we have producted 400 boards, There were almost 70 abnormal boards. When we download software into boards by MFGtools, it hangs on "Jumping to OS Image", and there is nothing at UART port (debug port). The other 330 circuit boards are OK,
the software can be downloaded successfully, and also these boards can boot from eMMC successfully.
We don't use DDR3 MT41K128M16JT-125:K from MICRON, and we use SCN15H2G1 60AF-13K from UnilC. SCN15H2G1 60AF-13K and MT41K128M16JT-125:K are with the same parameters such as max clock frequency 800M (DDR3-1600), 2Gbit (128M x 16) and so on. We have done DDR calibration, DDR pressure Test, update file "flash_header.s", rebuild our firmware and MFGtool's firmware ( uboot and kernal), replace the files
For 70 abnormal boards,what we have done are as follows:
1) We measure all the voltages and power-on sequence of the board, they are OK;
2) We do DDR pressure Test, and they are OK;
What's the problem? Why some baords are OK,and others are not OK?
Attachments are Mfgtoos.log and DDR's datasheet.