I have been experimenting with a Sparkfun “Thing” and have been easily able to program it to do what I want, with one exception: I cannot get it to interface with the outside world in any meaningful way. It appears that the voltage regulator cannot source enough current to light even a standard 5mm LED.
My project uses a switch closure to send a notification to my cell phone (via Blynk). I have a “virtual button” on my Blynk phone app that, when pressed, will light the green LED connect to pin 5 on the Thing …but I cannot make it do anything else. If I connect a standard LED to PIN 5 (or any other pin [changing the coding] of course) the LED does not light. It isn’t an issue of current sourced by my laptop: powering the thing from a 5v wall wart or the LiPoly battery gives the same result.
If I read your documentation correctly, the pins can only source 12 ma. Since a LED generally draws about 20 mA, the fact that one won’t light makes sense. Do you have any suggestions for interfacing the outputs?
I would try connecting the output to your “IOT power relay” but your documentation does not say how many mA are required to trigger the device
It appears that the voltage regulator cannot source enough current to light even a standard 5mm LED.
There should be plenty of leftover current available to light a LED. Where are you connecting the LED? Connecting between GND and 3V3 should do the trick.
I have a “virtual button” on my Blynk phone app that, when pressed, will light the green LED connect to pin 5 on the Thing …but I cannot make it do anything else. If I connect a standard LED to PIN 5 (or any other pin) the LED does not light.
Are you using a resistor with your LED to limit current? Without a resistor, the LED could potentially be drawing more current from the GPIO pin than the ESP is able to provide. You might try a 1K resistor. If that works but is too dim, add a second 1K resistor in parallel with the first and that should brighten the LED.
If I read your documentation correctly, the pins can only source 12 ma. Since a LED generally draws about 20 mA, the fact that one won’t light makes sense. Do you have any suggestions for interfacing the outputs?
If you’re using a LED that requires 20mA and won’t work satisfactorily with less current you’re going to want to use a transistor to drive the LED. That allows the ESP to use a minimum amount of current to ‘turn on’ the transistor and the transistor does the heavy lifting of providing more current to the LED. (Don’t forget to use a current limiting resistor to the LED, without that, the LED could be destroyed by excess current.)
I would try connecting the output to your “IOT power relay” but your documentation does not say how many mA are required to trigger the device.
I happen to have one of these at my desk and tested it. At 3.3 volts you only need about 1mA to trigger the relay. The IOT Relay does need to be plugged in and the power switch turned on for the relay to activate though.