Timeline for Why is my IR sensor giving wrong high voltage output?
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| May 21, 2018 at 9:33 | vote | accept | Kaushik Wavhal | ||
| Nov 15, 2015 at 22:50 | comment | added | vini_i | IR sensors pick up all kinds of noise, from the sun, from other IR sources, etc... This noise can commonly show up as random spikes in the wave form. To help reject that noise the IR stream is modulated. The modulation pulses the beam at a steady state. By sampling the wave form at a steady rate random spikes can be avoided. Be sure to sample at, at least, twice as fast as the signal. Also by sampling at a steady rate you have an easy time base to work with. If you use interrupts then you will pick up every spike and you have to create your own time base. | |
| Nov 15, 2015 at 16:06 | vote | accept | Kaushik Wavhal | ||
| May 21, 2018 at 9:33 | |||||
| Nov 15, 2015 at 15:59 | answer | added | John Wick | timeline score: 0 | |
| Nov 15, 2015 at 15:30 | comment | added | Kaushik Wavhal | @vini_i The MCU i am using doesn't have a hardware Analog input. So the software way is slow to read the pulses. What sort of noise will be introduced if i use the interrupt? Can it be avoided? | |
| Nov 15, 2015 at 15:26 | comment | added | vini_i | If you don't have an oscilloscope then the MCU is your best bet. Don't use an interrupt pin because you will pick up noise. Instead poll a pin at double or triple the speed of the modulation instead. | |
| Nov 15, 2015 at 15:23 | comment | added | Kaushik Wavhal | I am measuring the voltage with a standard digital multi-meter .I don't have a oscilloscope. So should i try connecting the sensor to the MCU to see if i receive pulses properly ? Do you think this can be a issue of high current supply (2A) ? | |
| Nov 15, 2015 at 15:15 | comment | added | user16324 | How are you measuring the voltage? A DMM is too slow, you need a scope to see if you're getting proper pulses. | |
| Nov 15, 2015 at 15:05 | history | edited | Kaushik Wavhal | CC BY-SA 3.0 |
added 10 characters in body
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| Nov 15, 2015 at 14:57 | review | First posts | |||
| Nov 15, 2015 at 18:19 | |||||
| Nov 15, 2015 at 14:55 | history | asked | Kaushik Wavhal | CC BY-SA 3.0 |