您好:
我们现在使用imx6solox的时候遇到了一些问题,能否麻烦您帮忙看看:
2)3个板子中有1个板子当USB_OTG1_VBUS供电5V,USB_OTG2_VBUS不供电时,在USB_OTG2_VBUS能测到一个4.5V的电压,怀疑是USB_OTG1_VBUS泄露过来的,VDD_USB_CAP测量值为2.4V左右
3)3个板子中有2个板子,在USB_OTG1_VBUS和USB_OTG2_VBUS都不供电的情况下,在USB_OTG1_VBUS上能测到1.8V左右的电压;将NVCC_3.3去掉以后,此电压降为0.4V左右,怀疑有从其他电源泄露;当USB_OTG1_VBUS供电5V时,VDD_USB_CAP默认值应为3V,实测电压为2.6V
5)JTAG能读写寄存器,单步运行时,PC指针一直在三个位置跳动。全速运行时,停止的时候PC指针一直指向一个位置。
板子的大概情况就是这样,附件为原理图,麻烦您帮忙分析一下,看看是什么问题,谢谢!
Hello jianming shi,
There is something wrong with your USB circuits. See below, please! you can debug it according to my advice:
1. Basic application USB OTG
--device mode.
USB OTG ID should be pulled up to 3.3V via 10K resistor, VBUS on connector and VBUS on CPU should be supplied by external USB VBUS( such as PC USB)
--host mode
USB OTG ID should be pulled down to Low, 5V VBUS on USB connector will supply external device.
2. You schematic.
(1) capacitor on VDD_USB_CAP
you can try to change C51 to be 4.7uF
(2) USB OTG1 VBUS & USB _2_VBUS
(3) VBUS on connector --- >VBUS on CPU
Please try to debug your board according to above suggestions!
In addition, 1.35v IS ARM CORE VOLTAGE, DON'T USE IT FOR OTHER PURPOSE!!
Have a nice day!
NXP TIC weidong sun
非常感谢您的回答,现在系统已经启动了,谢谢