Pulsed IR transmitter doubt

[Killstreet30]

 

Hello.

I had to interface an IR sensor for object detection and distance measurement but I'm using a normal IR transmitter and receiver and there's a lot of interference due to sunlight. So I want to pulse the IR transmitter and subtract the readings when it is on and off and remove that constant value so I'll be able to get the normal distance. So I thought that my above circuit will work and I will be using a timer function to pulse the IR transmitter but where I will I connect the timer port to? Because 5V is the input and the other terminal is ground. Please help. I thought instead of 5V if I connect it to the timer output but I'm afraid it'll be unable to drive the IR transmitter.

[Javier1]

>>but I'm afraid it'll be unable to drive the IR transmitter.

Did you tried already?

Im sure you could add another BJT to interface between 5v and 3v3, but just in case have you considered level shifters?https://www.mouser.es/ProductDetail/SparkFun/BOB-12009?qs=WyAARYrbSnb%252BGYLWggQnjQ%3D%3D&mgh=1&vip=1

[Killstreet30]

I haven't tried but one of my superior was telling it won't work so I was thinking of an alternate approach but I still feel it'll work because led needs a minimum threshold and I feel it'll be able to drive it. What do you think?

[AScha.3]

shure, it will work.

just your IR receiver -at vcc - will not work. outout should be at resistor. 🙂

but in general: drive a (typical) 30..40khz pwm -> out ,

and IR in -> AC-amp (DC cancelling, 1. opamp), followed by peak-rectifier ( 2. opamp) -> then ADC