ESP8266 Community Forum

- Wed Feb 22, 2017 11:40 am #62892

So I've seen plenty of adaptors which include pads on the underside for an LDO, but they all seem to lack pads for capacitors for the LDO.

You're talking about the white adapter plates right? You don't necessarily need to add capacitors because some of the newer ESP12 modules already include bypass capacitors within the module now.

It seems hard to find official schematics of the ESP12 modules but the ESP-12F is often shown including some capacitors, eg here, and I've used them fine with the white adapter plates and an XC6206 regulator and no other capacitors. ESP-12S's also include pullup/down resistors too and work fine with just a regulator.

- Wed Feb 22, 2017 4:11 pm #62897

You don't necessarily need to add capacitors because some of the newer ESP12 modules already include bypass capacitors within the module now.

I've used them fine with the white adapter plates and an XC6206 regulator and no other capacitors.

All boards, new and old, have capacitors. They would not be able to work if they didn't. Capacitors need to be at the chip. But that does not mean that the modules are built with enough capacitance. There still needs to be bulk capacitance close to the module. Yes the boards can work without adding them. But they may not work reliably under all conditions.

The XC6206 is only rated for 200mA and that is inadequate. When starting the ESP modules can require more than double that amount. Read the FAQ that Expressif has on the ESP8266.

- Wed Feb 22, 2017 4:52 pm #62898 I'm not going to argue Rudy but in my experience from having intermittent problems with older esp01's and esp12's with things random boot fails and waking up from deep sleep where they work fine for a few days or weeks and then just crash for no reason are gone nowadays. The newer esp12 modules like esp12S and using regulators like the xc6206 run rock solid. You can see Esp12 modules have evolved over time with new versions like the esp12e, esp12f, esp12q, esp12s etc, and see more internal bypass capacitors getting added internally in the schematics such as here to here to here to here.

- Wed Feb 22, 2017 7:45 pm #62903 I agree with you that they have been improving with every revision. And I would encourage anyone who is buying some now to get the ESP-12S (or ESP-7S). I am a little disappointed that the availability of the S series isn't as good as I had hoped it would be at this time. A search on AliExpress doesn't bring up any listings with the ESP-12S.

The issue I had with you comment was that you said that they are now including bypass caps. They always have. If you would had said they are finally adding more capacitance now then I would not have posted.

I still like to emphasize that a decent power supply is needed for these modules. There is a lot of information about the average current requirements but little as far as the maximum.