TUSB8044A: change from USB B to USB C

Hi,

TUSB8044A does not care whether the downstream connection is USB Type B or Type C. For USB 2.0 Type-C, typically the DP of the USB Type-C receptacle and DM of the USB Type-C receptacle are shorted together, so the enumeration behavior will be the same between USB Type B and Type C.

Thanks

David

Hi David,

sorry , what's DM and DP?  what's the full name?

Hi,

I am referring to the USB2 signal, D+ or D-.

Thanks

David

Hi David,

you mean the D+ and D- will short together, but how does it gonna transmit?

or did you mean  D+/- of  type-C will short to D+/- of type-B? 

just want to make sure

Fred

Can you please share a block diagram? I am not sure if I understand the question. I thought they want to replace the downstream Type-B connector to Type-C connector, is my understanding correct?

Thanks

David

Hi David,

here's the block diagram of their last generation ,

I think they're talking about the red circle part (USB2.0 KVM mux) ,

when "the MUX" suddenly switch from type-C 2.0 to type-B 2.0 signal in the diagram or vice versa.

usually  type-A will connect to mouse, type-B and C connect to desktop and notebook respectively. 

their current solution GL3590 has to wait 1ms delay to start handshake after mux switching. 

Fred

The USB2 enumeration is the same when you switching between USB Type-B and Type-C. But yo do have to make sure the VBUS is removed when switching between USB Type-B and Type-C.

Thanks

David

Hi David,

so looks like they still have to reset the USB_VBUS voltage to let HUB re-recognize right?

they pull low VBUS for a few ms and pull high again for their current solution