Hi,
I have query regarding i.MX8 M MINI power ups sequence. If you look at the power up sequence timing,
1. The minimum timing mentioned is '0' . Does that mean all supplies can come at once ?
2. Does RTC clock and RTC_RESET_B are must for serial download mode ?
I have another query which is related to serial download mode using USB. I am using USB1 as device only. I am not using USB_ID pin. This should not create any issue for serial download mode, right ? Second question is regarding USB_VBUS. According to i.MX8 datasheet, it should be 3.3V max. But if you see the NXP i. MX 8M MINI EVK board, it is at 5V level ( comparator is used to generate this voltage ). Need some clarification on this.
Thanks,
BR,
Sameer
Hi Sameer,
1. Not All. For example T1, means NVCC_SNVS_1P8 and VDD_SNVS_0P8 can come at once.
2. Yes
USB_ID floating is no problem.
There is an external resistor R108 . 30K so that the USB1_VBUS pin gets a lower voltage.
Have a nice day
Rita
Hi,
Regarding this topic I have two questions to ask.
1. I measured the timing parameter of the power on and off sequence but it differs from the NXP manufacturer's data sheet (PMIC part: PCA9450AAHNY; CPU part: MIMX8MM3CVTKZAA). Is there a problem with I.MX8M when there is such a discrepancy?
- Power-up sequence:
- Power-down sequence:
2. How can I fix this if I want the power-up sequence and power-down sequence times to be the same as the data sheet that NXP provides?
Thanks,
Henry
Hi Rita,
Thanks for your support. My issue is resolved. I can now successfully flash my board using USB as device.
Regards,
Sameer
OK. I am glad to hear that.