Does PSoC 5LP require an external crystal to support USB?

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JuNo_294036
Level 1
Level 1
        The datasheet for the USBFS component states that the PSoC 5 requires an external crystal and seems to suggest that this is not the case for PSoC 3 and PSoC 5LP. AN73503 http://www.cypress.com/?rID=57561 states that "Since the projects involve the use of USB component, in case of PSoC 5LP it is mandatory to use an external 24 MHz crystal." Is this a typo in AN73503 or should I include a crystal in my PSoC 5LP design if I intend to use the USBFS component? Julian   
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HeLi_263931
Level 8
Level 8
100 solutions authored 50 solutions authored 25 solutions authored

The PSoC5LP TRM states explicitely (Chapter 16, page 91):

   

 IMO has a USB mode that synchronizes to USB host traffic, requiring no external crystal for USB. (USB equipped parts
only)

   

So it can run without crystal.

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HeLi_263931
Level 8
Level 8
100 solutions authored 50 solutions authored 25 solutions authored

The PSoC5LP TRM states explicitely (Chapter 16, page 91):

   

 IMO has a USB mode that synchronizes to USB host traffic, requiring no external crystal for USB. (USB equipped parts
only)

   

So it can run without crystal.

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

AN57473 states http://www.cypress.com/index.cfm?rID=39404

   

 

   

This application note shows you how to do  simple data
transfer with PSoC 3 and PSoC 5LP using USB HID. The
PSoC devices include  a dedicated Full-speed (FS)
12 Mbps USB 2.0  peripheral, which uses an internal
oscillator –  a crystal is not required. The PSoC Creator
IDE and the USBFS  Component make it possible to
quickly build an application. A mouse and a joystick are
used as examples.

   

 

   

Regards, Dana.

ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

More confirmation -

   

 

   

http://www.cypress.com/?id=4&rID=58952

   

 

       

Regards, Dana.