SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
The transmitter module has a programmable delay line on each of the external signal inputs: TXCLK, TXD0, and TXD1. The delay elements introduce delays on the respective lines and are placed before the FSITX signals are sent to the TDM signal selection mux (controlled by the SEL_TDM_PATH signal). This is to facilitate adjustment for signal delays introduced by system level components such as signal buffers, ferrite beads, isolators, and so on, or board delays such as uneven trace lengths, long cable length, and so on. The length of the delay is controlled by setting the TX_DLY_LINE_CTRL register values for each line. By default, no delay is introduced by the delay line elements. The delay values should only be adjusted while the FSITX is held in soft reset, ensuring that there are no active transmissions during this process. Figure 7-311 shows a representation of the delay line circuitry for the input signals. The implementation for TXCLK, TXD0, and TXD1 are replicas of this diagram. All circuits will behave similarly.
For more information on skew compensation, refer to the Fast Serial Interface (FSI) Skew Compensation Application Report.