Flashing Issue with ESP32-C3 Module (M4N4) – Chip Revision 4

[tallal]

Hi,

We're encountering a flashing issue with the ESP32-C3 module variant M4N4 (chip revision 4), while the older XXN4 version flashes without problems. Our PCB manufacturer confirmed the issue occurs only with the newer M4 revision.

According to Espressif's PCN20220101, the chip revision was upgraded from 3 to 4, with no impact on performance or software compatibility, and IDF should support it.

Could anyone clarify:
1. What could be causing this flashing issue specifically with the M4N4 modules?
2. Are there any known changes in boot mode or flashing procedure for chip revision 4?
3. Could this cause field reliability issues after programming?

Any guidance or fixes would be appreciated.

Thanks.