D is for Diode

automatic captions, checked for structure and key terms; corrections welcome

[00:00:00.000] [unclear opening audio]
[00:00:34.280] Hey, Woz, what you doing?
[00:00:36.080] Oh, hi, Adabot.
[00:00:37.020] I was just adding some protection to this circuit.
[00:00:39.720] Interesting.
[00:00:40.420] Why does this circuit need protection?
[00:00:42.180] Well, a circuit needs to be protected for a couple of reasons.
[00:00:44.800] One example is if I were to connect a battery to this incorrectly,
[00:00:47.960] then electrical current might flow in the wrong direction
[00:00:49.840] and damage some of the components.
[00:00:51.620] Oh, no.
[00:00:52.440] How do you make sure that doesn't happen?
[00:00:54.140] Well, we use a diode.
[00:01:00.260] By placing a diode at the circuit's power input,
[00:01:03.000] we ensure that the current can only flow in one direction,
[00:01:05.760] the correct direction that we've designed the circuit to work with.
[00:01:12.500] So a diode is like a one-way street for electrons?
[00:01:15.960] Exactly!
[00:01:16.780] The electrons can only flow through the diode in one direction,
[00:01:19.280] and they have a really hard time going back the other way.
[00:01:26.100] The stripe indicates which end of the diode acts like a wall
[00:01:28.800] to block the electrons.
[00:01:35.000] Diode protector of circuits.
[00:01:37.600] Yes, but diodes do more than just protect circuits, Adabot.
[00:01:40.860] Oh, what else do they do?
[00:01:42.720] Well, some diodes emit light when we pass current through them.
[00:01:45.840] We like to call these light-emitting diodes, or LEDs for short.
[00:01:50.000] Maybe you've heard of them?
[00:01:52.140] LEDs? I love LEDs.
[00:01:54.540] I thought so.
[00:01:56.580] So that's what D stands for in LED. D stands for diode.
[00:02:01.180] That's right. Well, it looks like this circuit's all done. How about we go test it out?
[00:02:08.340] Adabot, are you coming?
[00:02:10.460] Sorry, Woz. I'm an electron in a diode. I only go in one direction.
[00:02:15.800] Ow.
[00:02:18.020] Ow.
[00:02:19.980] Oh, Adabot, let's go.