menuconfig option: VDDSDIO LDO voltage

[zliudr]

Could someone explain this option please? I thought VDDSDIO is either 1.8V or 3.3V. What is the 1.9V here? I've been using WROOM with this setting untouched until I saw it today and don't know what it does. I've just upgraded to WROVER-B module that seems to not connect a resistor to enable 1.8V VDDSDIO. How is this option related to WROOM, WROVER, and WROVER-B?

I'm using ESP-IDF V3.3

[mikemoy]

https://docs.espressif.com/projects/esp ... sdio-boost

[zliudr]

https://docs.espressif.com/projects/esp ... sdio-boost

So no effect for 3.3V SPI FLASH. Thanks.