ESP8266 Community Forum

- Sun Aug 16, 2015 2:27 pm #26203

I can't decipher the role of the IC on the far right

It is probably a diode bridge, since it is very near of the AC wires ...

It is, an MB10M. The thing in blue is actually a 2.2nF 1KV capacitor. The small diode is definitely a zener ... i soldered that one on myself Without something like a zener what would be controlling the output voltage?

- Sun Aug 16, 2015 5:10 pm #26218 Each device is different.

Not all of them just have a zener, but the cheaper ones I have seen, do just have a single zener.

I have sucessufully modified several of them.

The zener is part of a feedback circuit which controls the HT side of the PSU, its not regulating the LT side like a linear regulator.


BTW. WARNING. dont run it with the zener removed. As without the controlling feedback, you are likely to destroy the PSU.

- Sun Aug 16, 2015 7:57 pm #26228 Thanks to all for an interesting discussion. This gives me a couple approaches which could apply in different circumstances.

With the AC-DC buck converter modules off EBay, is a 600mA enough? I've seen 1A power supplies recommended for ESP8266 modules.

- Sun Aug 16, 2015 8:11 pm #26229

With the AC-DC buck converter modules off EBay, is a 600mA enough? I've seen 1A power supplies recommended for ESP8266 modules.

The issue is not the continuous power usage of the ESP8266. IteadStudio's wiki quotes it at 215mA when transmitting.

http://wiki.iteadstudio.com/ESP8266_Serial_WIFI_Module

The issue is the spikes of current that it takes, which could be in excess of an amp.
But the solution to this is to use decoupling capacitors. I'm not sure what the normal value is.

I have seen values quoted at 1uF , which seems reasonable. I use 33uF but I just happened to have that size lying around on my bench