#6 The Diode [Post Homework Here]

Talk about the first PyroEDU course here.
ThePyroElectro
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#6 The Diode [Post Homework Here]

This week's course is now up and ready for you to watch:
http://www.pyroelectro.com/edu/basics/diode/

STLShawn
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Re: The Diode [Post Homework Here]

HOMEWORK QUESTION 1
What are some differences between an LED and a rectifier diode?

HOMEWORK QUESTION 2
Which way does electrical current flow through a standard diode?
From Anode to Cathode.

HOMEWORK QUESTION 3
What is the circuit symbol for an LED? for a standard diode?
OK, can’t post it in text, here’s a pic.
Diode

LED

HOMEWORK QUESTION 4
Which side of a diode component has a straight line marking, the cathode or anode? Why?
Straight line marks cathode side. A diode is single direction.

ThePyroElectro
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Re: The Diode [Post Homework Here]

STLShawn wrote:HOMEWORK QUESTION 1
What are some differences between an LED and a rectifier diode?
...
...
Straight line marks cathode side. A diode is single direction.

Hi Shawn,

I didn't see an answer to #1, did you need some hints? Everything else was right!

If you're curious about 'other' types of diodes. Another more tricky type is called the Zener Diode:
http://en.wikipedia.org/wiki/Zener_diode

These are often used as small voltage regulators (keeping voltage steady) and also have a multitude of uses in RF/Analog circuits.

jonnyquin
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Re: #6 The Diode [Post Homework Here]

HOMEWORK QUESTION 1
What are some differences between a LED and a rectifier diode?
LED emits light when conducting, whereas rectifier diode doesn’t emit.

LEDs are often used as light sources, and rectifier diodes are used in rectifying applications.

Materials used in rectifier diodes and LED’s have different properties.

HOMEWORK QUESTION 2
Which way does electrical current flow through a standard diode?
From anode to cathode
HOMEWORK QUESTION 3
What is the circuit symbol for an LED? for a standard diode?
This is the standard diode:
This is a Led:
http://2.bp.blogspot.com/-rC1F8Ea4Qng/U ... symbol.png
HOMEWORK QUESTION 4
Which side of a diode component has a straight line marking, the cathode or anode? Why?
Cathode, because it is the negative side of the diode

ThePyroElectro
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Joined: Mon Nov 12, 2007 9:24 pm
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Re: #6 The Diode [Post Homework Here]

jonnyquin wrote:HOMEWORK QUESTION 1
What are some differences between a LED and a rectifier diode?
LED emits light when conducting, whereas rectifier diode doesn’t emit.

LEDs are often used as light sources, and rectifier diodes are used in rectifying applications.

Materials used in rectifier diodes and LED’s have different properties.

HOMEWORK QUESTION 2
Which way does electrical current flow through a standard diode?
From anode to cathode
HOMEWORK QUESTION 3
What is the circuit symbol for an LED? for a standard diode?
This is the standard diode:
This is a Led:
http://2.bp.blogspot.com/-rC1F8Ea4Qng/U ... symbol.png
HOMEWORK QUESTION 4
Which side of a diode component has a straight line marking, the cathode or anode? Why?
Cathode, because it is the negative side of the diode

JohnOO
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Re: #6 The Diode [Post Homework Here]

Hello there,
Sorry if this is the wrong place to post this, but I have had problems with the trim pot, it blew 2 LEDs on me while I was adjusting the screw in the first circuit experiment in the lesson video. Any advice on what I might have done wrong?

ThePyroElectro
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Re: #6 The Diode [Post Homework Here]

JohnOO wrote:Hello there,
Sorry if this is the wrong place to post this, but I have had problems with the trim pot, it blew 2 LEDs on me while I was adjusting the screw in the first circuit experiment in the lesson video. Any advice on what I might have done wrong?

Possibility [1] you are connecting the LED directly to power.

Possibility [2] the trim pot is at the lower resistance setting < 100Ω. After a few minutes at this setting it could damage the LED. If the trimpot is all the way down to 0Ω (meaning turned the knob the entire way) you will eventually damage the LED as it is almost completely connected to power.

If you're interested in learning about electronics, you might buy a bag of 1,000 LEDs off ebay for \$15-20 and keep them in your tool box. Blowing LEDs out, while not ideal, can happen a lot when you're learning and prototyping.

JohnOO
Newbie Pyro
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Joined: Mon Oct 27, 2014 10:20 pm

Re: #6 The Diode [Post Homework Here]

ThePyroElectro wrote:
JohnOO wrote:Hello there,
Sorry if this is the wrong place to post this, but I have had problems with the trim pot, it blew 2 LEDs on me while I was adjusting the screw in the first circuit experiment in the lesson video. Any advice on what I might have done wrong?

Possibility [1] you are connecting the LED directly to power.

Possibility [2] the trim pot is at the lower resistance setting < 100Ω. After a few minutes at this setting it could damage the LED. If the trimpot is all the way down to 0Ω (meaning turned the knob the entire way) you will eventually damage the LED as it is almost completely connected to power.

If you're interested in learning about electronics, you might buy a bag of 1,000 LEDs off ebay for \$15-20 and keep them in your tool box. Blowing LEDs out, while not ideal, can happen a lot when you're learning and prototyping.

Thanks very much for the reply!
With possibility [2], I turned the trim pot partly towards 0Ω, and the LED died. Oh well, probably made a silly mistake without realising.