SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Two clocks are provided to the MCAN module:
Within the MCAN module there is a synchronization mechanism implemented to ensure safe data transfer between the two clock domains. There are synchronization between the signals from the Host clock domain to the CAN clock domain and vice versa and between the reset signal (MCAN_RST) to the Host clock domain and to the CAN clock domain.
MCAN_ICLK must always be higher or equal to MCAN_FCLK, in order to achieve a stable functionality of the MCAN module. Here, also the frequency shift of the modulated MCAN_ICLK has to be considered:
f0,ICLK(OCP) ± ΔfFM,ICLK(OCP) ≥ fFCLK
CAN-FD supports higher speeds of operation and as such has more stringent timing requirements than Classic CAN. For optimal performance, TI recommends using the lowest N-divider value that maintains a working PLL REF_CLK (GMAC_DSP_DPLL_CLK) for the system. Lower N-divider values increase the loop bandwidth of the PLL which in turn improves timing margins for CAN-FD.
For CAN-FD operations > 2 Mbps:
For CAN-FD operations < 2 Mbps:
For more information on how to configure the relevant clock source registers, see Chapter 3, PRCM and the device data manual.