I'm currently doing an electrical engineering course. I mute the lecturer to listen to your explanation instead. Terrible isn't it. But thanks very much for putting these up.
Ohh the electrons from the negative terminal (electron flow) fills out the holes in p type material. Conversely the electrons from the n type side is reaching towards the positive terminal of the battery so the depletion layer is increased and if we finished this process then the current would not flow in a reverse bias mode.
Oh never mind. I was wrong my self. Because of the charge double layer, which results out of the will of the to potentials to get equivalent, the electrons forming on the p-side are directe moving to the n-side because the first space on the n-side is positivly charged. The result in the end is a potenzial difference and a resulting current.
@@atomicreactions9201 are you talking about reverse or forward bias mode?? Like I would recommend you to watch a video on diodes by ochem tutor on youtube. So that you get the basic concept and come back here and watch solar cells,photodiode and led.
Couple of hours reading universities texts and nope. watch this video twice, plus the previous one and got it. Online universities (and brick) are so behind in teaching.
Tomorrow is exam of 8th semester Thank you Sir ji! you cleared my concepts even my professor could not clear the concepts in the timeframe of 6 months you did it in 11:39 minutes. What a Legend! Lots of Love from Pakistan!
Sir at 07:43 You mentioned that we want the current only due to light so we don't use forward biasing (as another current flows) But in reverse biasing, a current flows (not due to photons) but it's very small. So we are neglecting that current, right?
The heck bro, the only few channels that post teaching videos other than Hindi in India. This channel is for indians not for North Indians alone so shut up😡🤬🤬🤬🤬🤬🤬🤬
00:02 Photodiodes convert light to electricity and are used in detecting brightness 01:39 Reverse biasing in photodiodes limits current and widens depletion region. 03:08 Light absorption in semiconductors creates electron-hole pairs 04:32 Light absorption generates current in semiconductors 06:01 Photodiodes detect brightness using reverse bias. 07:27 Photodiodes work in reverse bias to ensure current is only due to light. 08:54 Current generated by photodiodes is independent of voltage after a certain point due to the number of electron-hole pairs formed by the light. 10:15 Photodiodes can generate a tiny current even in absence of light due to thermal energy.
It makes no sense to me that the free electron would recombine outside of the depletion region, because we apply an electric field with our reverse bias. Or what do I see wrong?
Possibly if you have some bright light shining at the sensor and you happen to block that light when you come near the door, current will decrease, and door can open, but I think this can raise many false alarms. Like what if a fly just cover up the sensor, or something.
Dear Sir, I have a problem which you may be able to help me solve. I have a new Solar Panel installation and I want to use it in part to heat my underfloor heating through the electrical conduction wires embedded in my concrete floor. The problem is, when sunlight dims during the day, electricity comes from the grid to maintain a consistent flow of electricity to heat my floor. Grid electricity is expensive and I NEVER want to use grid electricity to heat the floor, only solar derived electricity. I was thinking of combining two devices to make a switch that turned on the output to the floor from my solar panels when the sun is shining and turn off current when the sun is not shining. The thought was to use a Photodiode as the current switch that is connected via a low voltage power supply to a solenoid. This solenoid switches off 240V power to my underfloor heating when the solar radiation {and therefore current in the low voltage circuit} drops to below a certain level and stops power going to the heater circuit. If the sun reappears from behind a cloud, the circuit goes back on again. What do you think about my problem and do you have any suggestions? Thanks.
