USB3.1 10Gbps Dual-Channel Linear Redriver
Created: Aug 15, 2016
No description available.
When signals from the USB travel across a PCB or a cable, signal integrity degrades due to loss and Inter-Symbol Interference (ISI). Due to these problems, it is necessary to use a linear redriver or a linear equalizer. The linear redriver compensates for the channel loss, and hence, extends the channel length and enables systems to pass USB compliance. This design features the TUSB1002 USB3.1 10Gbps dual-channel linear redriver from Texas Instruments. The TUSB1002 is both a USB 3.1 SuperSpeedPlus (SSP) redriver and a signal conditioner.
This circuit is designed as medium connection between a USB host and a USB device. The interface to this design consists of a USB 3.1 type-B receptacle as the input and a USB 3.1 type-A receptacle as the output. Therefore, in order to connect this to a system set up, 2 USB 3.1 Standard Type-A → B cables are needed. The TUSB1002 differential receivers and transmitters have internal bias and termination. For this reason, the TUSB1002 must be connected to the USB3.1 host and receptacle through external AC coupling capacitors. In this design, 0.1uF capacitors are placed on TX2P/N and TX1P/N. The TUSB1002 has (MODE, CFG1, CFG2, CH1_EQ1, CH1_EQ2, CH2_EQ1, and CH2_EQ2) 4-level inputs pins that are used to control the equalization gain and the output voltage swing dynamic range.
This design is useful in applications wherein cable length is an issue. This can be used in notebook, desktop PCs, TVs, tablets, cellphones, active cable and docking stations. Furthermore, this offers programmable equalization that extends the interconnect distance between two devices. Also, the device supports low-power modes when unplugged. The design can also function in USB compliance mode to test the transmitter for compliance to voltage and timing specifications per USB 3.1 compliance specification. Since the TUSB1002 has two independent channels, it can be optimized to correct ISI in both the upstream and downstream directions.