SPI Flash

ESP32-C3 supports external flash of up to 16 MB, which is mainly used for storing program firmware, system parameters, user parameters, user data, etc. The SPI flash is powered by VDD_SPI. We recommend reserving a serial resistor (initially of 0 Ω) on the SPI line, to lower the driving current, adjust timing, reduce crosstalk and external interference, etc. ESP32-C3FH4/FN4 has an in-package 4 MB SPI flash.