Tool/software:
It's first to use USB2 redrive. From the picture of datebook, the D1P is connected to D2P on the PCB, and same connection to D1M and D2M. My question is that the connection of D1P and D2P is happened in the TUSB211A or on the PCB? If D1P is connected to D2P on the PCB, how does TUSB211A amplify USB signals? Does it amplify the signals of the entire link?
Hi Feng,
The connection of D1P to D2P and D1M to D2M needs to be done on the pcb below the redriver, with the D1/2 P/M pins of the redriver touching the DP/DM lanes. The picture below is an example of what the layout should look like for that:
The TUSB211A and the rest of our USB2 family of redrivers works by monitoring the DP/DM lanes of the USB2 signaling, waiting for the signal to indicate both an active connection and a HS connection, via a successful HS handshake. Once it sees this connection, the USB2 redriver enables, injecting currenting into the USB2 signal as it moves underneath the redriver which aims to boost the AC aspect of the signal (Rising/falling edge) and the DC aspect of the signal (Vhigh and VLow). This helps increase the margin of the signal in something like an eye diagram or compliance test, boosting the overall length the USB2 signal can support.
Please let me know if you have any other questions.
Thanks,
Ryan
