FX2 device recognition error

[DoLe_3240391]

Hi

I have a design module with CY7C68013a controller.

Most of the time the device including software is working well but sometimes it seems that the there is a recongnition problem.

If using a USB cable for 2 m PCB connection, it will work properly.

However, if connecting an extension cable longer than 3 m to this cable, it will get an recongnition error.

The extension cable is a repeater and can be connected to the power adapter.

3.3V, which is the driving voltage of controller, was confirmed to be normally input.

Why would a device recognition error occur only when an extension cable is connected?

How do I fix it?

Friendly regards

Dongyeol

[YatheeshD_36 · Accepted solution]

Hello,

Please make sure that all the VCC and AVCC pins get the desired voltage of 3.3 V. High speed device will draw a maximum of 500 mA, please make sure that the cable is capable of carrying this current.

Try using a single 5m cable, as per the USB spec the maximum length of the cable that can be used for high speed devices is 5m and there may be signal integrity issues when connecting two cables.

Best Regards,

Yatheesh