ESP8266 Community Forum

- Mon Jan 18, 2016 3:00 am #39127 Hi xtal,

Thanks again.

... how can this be a problem? There should be plenty of 3.3v power. I've just ordered some level converters. I hope it will fix the problem.

I'm still wondering why this isn't mentioned elsewhere?

- Mon Jan 18, 2016 1:03 pm #39163 The problem is the logic level of the usb converter which normally uses 5 volts ....
So the switching point is quite possibly around 2.5 volts [ie] 0-2.5 = 0 logic level 2.5-5 = 1 logic level
The 3.3 device , it's 1 level may be 1.5 volts which would look like a 0 to the usb converter...

Some usb converters have a 3 volt jumper ,, I don know how reliable they are...

Like wise the usb TX logic high level is 2.5 or greater feeding your 3.3 device, and could damage your 3.3 device
Although some have claimed They have had no damage,,,,

Its better to be safe than sorry so use a level shifter...

- Tue Feb 02, 2016 2:32 pm #40296 Hi there,

So, it took me a while but I ordered some components; a levelshifter, CD210 and some LM1117's!
I have hooked the LevelShifter to [HV] to de FTDI side (5v) and the [LV] to the ESP with the GND connected and a external 3.3v power adapter -> No response!
I also tried a CD210-> No response!
I've also hooked the a 5v FTDI to a LM1117 voltage regulator -> No response!

Even no serial crap characters...

But, still no response at all! What's wrong? I feel very sad. Do you have any suggestion?

Thanks