POWERON port in STPC VEGA

granitvt · ‎2005-07-01

Posted on July 01, 2005 at 12:02

granitvt · ‎2005-06-29

Posted on June 30, 2005 at 08:21

Hi

I use STPC VEGA CPU on my board (STPCV1JEBC and STPCV1KEBI). POWERON signal (in schematic - USB_POWERON) have level 1,8V for logic ''1'' (in both CPU), but in STPC VEGA datasheet this output port is ''LVTTL Output, 4 mA drive capability, Tri-State Control''. Pull-up resistor (1K) does not effect for this level. All power switch for USB (including TPS2014) have 2,0V minimum input level for ''ON'' input (in datasheets). Is this defect on chips ?

kaouther · ‎2005-07-01

Posted on July 01, 2005 at 09:32

In our schematics, on the USB_OCsignal there is a pull up resistor (1K) that is puled to 5V also in the datasheet. There is no defection on chip.

Do you dsigned board and you faced issues with USB?

This is implemented on our vega evaluation board and the USB is validated and works with no problem. Also , other customer using the same implementation on their design and there is no problem. Check your hardware if you have some issue abd reffer to our implementation.

Regards.

granitvt · ‎2005-07-01

Posted on July 01, 2005 at 12:02

Hi

Thanks for the answer, but I say about POWERON port, not USB_OC (USB_OC work with no problem). POWERON port drive the power switch on USB, but have low level (1,8V = VCC core) for logic ''1''.