SPRUJE4D August 2024 – June 2025 F29H850TU , F29H859TU-Q1
The on-board 25MHz clock can be used to clock the F29H85x MCU. However, when this clock is used, clock glitches can be induced in the MCU device that can lead to a fault state. See the F29H85x and F29P58x Real-Time MCUs Silicon Errata for more information.
To work around this issue, the on-board 25MHz clock can be disabled by removing R30 and populating R33 with a 10kΩ resistor. The internal oscillators (INTOSC1 or INTOSC2) of the MCU must be used as the main clock source. The INTOSC frequency accuracy must be carefully considered for certain peripherals and applications.
Additionally, when the workaround modifications are implemented the EtherCAT PHY clock outputs (PHY0_25MHZ_CLK and PHY1_25MHZ_CLK) are also disabled and EtherCAT PHY communication is not supported.