SLLA558 May 2021 TUSB211 , TUSB212 , TUSB216I
The TUSB216I has a new RX_SEN setting (pin 9) to help recover signals in high loss environments. In most applications this pin can be left disconnected for the mid RX_SEN setting. The mid RX_SEN setting is used in most applications with typical USB 2 signal amplitudes. Tuning this setting is recommended when the expected signal as seen at TUSB216I USB data pins amplitude is outside the normal range. TUSB211 does not have this function.
The recommendation is to start with mid RX_SEN setting and then move to high or low settings based on the signal amplitude as measured at the TUSB216I. For example, if the signal amplitude is low after the signal traverses a very long cable, use the high RX_SEN setting. For the TUSB216I to recognize any change to the RX_SEN setting, the RSTN pin must be toggled.