An emitter follower to isolate MCU from load?

Question

I am trying to drive an LED strip (10 LEDs) from the output of an ESP8266 GPIO pin. I measured the short circuit current from the GPIO and got around 40 mA. My question: Is it recommended to include an emitter follower stage to isolate my ESP8266 and my load (LED strip)? I don't want my load to draw a large current from the MCU pin which could alter the logic level.

A crude circuit is shown below (component values are not as per calculation)

^{simulate this circuit – Schematic created using CircuitLab}

Answer 1

You do it as simple as this:

^{simulate this circuit – Schematic created using CircuitLab}

The 1kΩ resistor at the base of the transistor feeds about [email protected] into the small signal NPN transistor, that's enough to saturate it for a collector current of up to 100mA. If you need more than that, consider a darlington NPN instead. VLED may be up to 50V or so, whatever your small signal NPN offers.