ESP32-LyraT-Mini schematic - Grey parts?

[Willybood]

Good morning.

I've been working on a new PCB design based on the ESP32-LyraT-Mini. Its schematic (https://dl.espressif.com/dl/schematics/ ... 190605.pdf) has a bunch of components that are light grey, some of which don's appear to be on the board. Why are they on there? Why are they marked differently?

Thanks for your help.

[ESP_krzychb]

Hi Willybood,
Welcome to the forum and good afternoon
Components with names grayed out are optional and not installed.
They also have (NC) in the name (no component)
For example U2 ESP32-WROOM-32D(NC) is a cheaper version of ESP32 module without PSRAM that may be used instead of ESP32-WROVER-B, if your application does not require PSRAM.