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output for ir sensor

Topic last updated 03 May 2016, by Nick Marsh. 1 reply
amirul lan
03 May 2016

how can i connect two different LEDs as the output of signal of IR sensor?

- sensor detect, red = 1, green = 0 - sensor not detect, red = 0, green = 1

Nick Marsh
03 May 2016

Hi,

A Simple Circuit ? is dimm ok ? /media/uploads/Diablo550/simple2leds.png

Red Led has approx 2.2V drop Green Led has approx 2.0V drop

This is not a normal circuit for this function, but because the LEDs add to 4.2V, they will not conduct together.

Approx 1V across the 1K resistor is 1mA it's not bright.

Using 200R will be ok, but you are stressing the pocessor power budget at 5mA.

So, dimm it shall be...

or use one transistor inverter for 50mA or more,

or to be very bright

add another two transistors to drive both LEDs hard.