Hello,
My first electronics PCB project has an Omnivision CMOS (7740) and some Infrared 850 LED's nearby (1 cm from cmos chip).
I'm getting noise in image when I turn on lights which you can clearly see in the image posted (with PWM or solid on), and I can't figure out if it's the light bleeding through the PCB and getting to the sensor, or if it's electrical noise somehow. I don't have LED traces near the sensor traces, but they do share the negative.
I've tried to block the light with plastic parts surounding the LED's, but the IR light seems to end up everywhere.
If it's physical what do I need to do to block it in PCB design, and if it's electronic, same question.
Appreciate anyones review of this.
Brent
My first electronics PCB project has an Omnivision CMOS (7740) and some Infrared 850 LED's nearby (1 cm from cmos chip).
I'm getting noise in image when I turn on lights which you can clearly see in the image posted (with PWM or solid on), and I can't figure out if it's the light bleeding through the PCB and getting to the sensor, or if it's electrical noise somehow. I don't have LED traces near the sensor traces, but they do share the negative.
I've tried to block the light with plastic parts surounding the LED's, but the IR light seems to end up everywhere.
If it's physical what do I need to do to block it in PCB design, and if it's electronic, same question.
Appreciate anyones review of this.
Brent
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