I am currently working on an ESP8266 based module. I took the schematic from the datasheet ESP8266.
Here is a picture:
The problem is that it doesn't work. To make sure it's not the software or the components, I've taken the components from another ESP8266 module (ESP-01 which I've tested) and soldered them on my custom board.
Since there are no pins on my board to test whether the antenna does not establish a connection or the chip doesn't work at all.
Actually, I have followed all the rules. The crystal is more than 0.8mm away from the pins but not too far away. The paths are about the same length and have no vias.
My biggest suspicion is the capacitor between ESP and antenna. In some schematics there is an inductor or the capacitor has a different value each time. It is very confusing.
I would be very happy if you could help me!
- VCC = 3.3V
Chip Antenna: Rainsum an6520
The xtal path goes first into the capacitor and then into the crystal