PSoC 5, 3 & 1 MCU

[JuNo_294036]

        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   

[HeLi_263931 · Accepted solution]

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.

[ETRO_SSN583]

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]

More confirmation -

       

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

           

Regards, Dana.