USB Thumb drive Pull up resistors

[shiweiluan]

Hi, when I read the USB Thumb Drive schematic, I found there is no pull-up resistors on D+ or D- (DMH, DMF, DPH, DPF pins). The overview says it is USB2.0 high speed and full speed Compliance (refer to USB Thumb Drive Reference Design|Freescale).

But if I plug it into computer, will it be recognized as high speed or full speed  and how?

Thank you in advance.

Shiwei

[iggi]

Hello,

as far as i know, it depends on the host i.e. a PC in this case.

Difference Between USB 2.0 Full Speed and USB 2.0 High Speed Devices:

- USB 2.0 full speed is transferring data at the same speed as USB 1.1 full speed (12Mbps), but uses protocols that allow for faster devices to be connected to the same hub or system on newer (now older) model computers in the market.
- USB 2.0 high speed is transferring data at (480Mbps).

Regards,

iggi