ESP32 Forum

Hi,

I am going to make a pcb design using ESP32-U4WDH chip instead of its modules. In the documentation I found that this chip contains 4 MB of flash built-in to it. When I was refering to circuit design as attached in the image, it describes that "In cases where ESP32-U4WDH with in-package quad 3.3 V flash is used, the in-package flash is connected as Figure ESP32 Schematic for Quad 3.3 V In-Package Flash shows."
My question is if this chip already contains a 4 MB flash, do I still need to expose these connections or I just add ESP32-U4WDH chip? If yes, what is the model number or part number of this 4 MB flash?
2nd question is is there any effect of not using external PSRAM as I don't want to add this?
From this design, I actually don't wanna use external flash and external PSRAM in my design and want to know if it works without these components.
https://docs.espressif.com/projects/esp ... -schematic

If the chip has in-package flash, you don't need any external memory chips.
And you don't need to connect/expose the pins the internal flash is connected to. In fact, the flash being internally connected to the pins means that you should not connect anything else to these pins (except for external PSRAM, if you want that.)

The only effect of not having external PSRAM is that you don't have external RAM. If your application doesn't use external RAM, i.e. the internal RAM is big enough, there's no benefit in adding a PSRAM chip to the design.

Thank you very much for the response. In that casse, I am not exposing the pins as I think 512 kB of RAM and 4 MB builtin memory are enough.