ESP32-WROVER vs. ESP32-WROVER-E Compatibility (HW & FW)

[bobbygz]

My company has a design in process using the ESP32-WROVER and we just discovered that this part is "Not Recommended For New Designs." The ESP32-WROVER-E using the third generation CPU appears to be a drop in replacement. Are there ANY functional differences between these parts that would require modifying our PCB or firmware? (We are still using V3.3 of the ESP-IDF). Thank you in advance.

[mvduin]

The changes I've spotted:

Pins 17-22 of the module (SHD/SD2, SWP/SD3, SCS/CMD, SCK/CLK, SD0/SD0, SDI/SD1) have been disconnected, since the corresponding esp32 pins are already used for the module's integrated flash and psram. Previously the datasheet merely stated these pins "are not recommended for other uses".

The supply voltage for the flash and psram (VDD_SDIO) has been changed from 1.8V to 3.3V. Consequently:

• removed 10 kΩ pullup from GPIO12 (MTDI), which is the strapping option for selecting the VDD_SDIO voltage (if not overridden by efuse)
• removed 2 kΩ pulldown from VDD_SDIO

Various minor changes in accordance to current hardware design guidelines:

• added 499 Ω series resistor on U0TXD ("in order to suppress the 80 MHz harmonics")
• removed 270 pF capacitors between SENSOR_CAPP and SENSOR_VP and between SENSOR_CAPN and SENSOR_VN ("high-precision ADCs are not supported")
• some changes to power supply filtering