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USB low-full-high speed peripherals

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AN15456-Guide to a Successful EZ-USB® FX 2LP ™ Hardware Design for 3.3 testing below

They are thinking of checking the operation on the board equipped with FX2LP according to the following test items, but could you please tell me  the detailed test procedure for each test item?

3.3 Testing
Any USB reset circuit should be thoroughly tested. The following tests are recommended:
▪ Cold power up, plugged into USB
▪ Cold power up, unplugged from USB

Q1) There is a Cold power up in the state at the time of the above test, but please tell me specifically what kind of state it should be before plugged and unplugged.is it ok to think that it mean that only the FX2LP board is powered off before plugged/unplugged? 

Q2) Also, please tell me specifically what to check after plugged and unplugged.

▪ Hibernate / resume, plugged into USB
Q3) Please tell me the specific test procedure for the above.

▪ Power cycle, plugged into USB
Q4) Please tell me the details about Power cycle. Also, please tell me the specific test procedure above.


Best Regards

1 Solution
Moderator 250 solutions authored 500 replies posted 250 replies posted


Yes, cold power-up means powering on from a powered-off state. It should previously be in a powered-off state.

You should check if the reset circuit is following the specifications as mentioned in the datasheet and app note.

You need to check the reset timings in suspend mode and by power cycling (off - on) the device.



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