Our product based on cy7c68013a.
Most of them are Normally operating well. But some product did not be recognized about 2~3 times out of 10.
Power source, reset timing, i2c clk, data lines were good. However,there was someting very strange about i2c data voltage abnormal.
There was no pull up, or data transaction, but voltage level about 1.4v with pull down sometimes.(our voltage level 3.3v)
I haven't seen this symptom. Would you tell me how to debug this symptom? Wold you tell me how to solve this problem?
Please refer to the document and ensure that the schematic is according to the KBA: https://community.cypress.com/t5/Knowledge-Base-Articles/Schematic-Review-Checklist-for-EZ-USB-FX2LP...
Kindly provide your schematic for review.
I understand but kindly provide your schematics for a quick review once.
Also, please elaborate on the issue which you are facing.
here, It is schematics for cypress circuit. I think it doesn't cause a problem.
And Issue is that USB Device Not recognize happened sometimes (about 2~3 times out of 10).
When this device recognized normally, all operation is perfect. but Unknown USB Device status happened sometimes...
>> Can you please let me know if this behaviour is being displayed by 1 board or all the boards?
>> Is this issue seen with all the PCs?
>> As you mentioned that about 2-3 times the device does not gets recognized. From here, how are you bringing it back to working mode?
1. I just displayed cypress circuit. I know that USB device recognition is a part of cypress work.
3. When the device dos not gets recognized, I can not do anything. So, I just power off and on and then it recognize well again. It is Very strange symptom..