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#6 The Diode [Post Homework Here]

Posted: Thu Nov 29, 2012 8:24 pm
by ThePyroElectro
This week's course is now up and ready for you to watch:
http://www.pyroelectro.com/edu/basics/diode/

Post your homework answers here to compare with everyone else!

Re: The Diode [Post Homework Here]

Posted: Mon Dec 03, 2012 12:27 am
by STLShawn
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.
http://upload.wikimedia.org/wikipedia/c ... ol.svg.png
Diode

http://upload.wikimedia.org/wikipedia/c ... ol.svg.png

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.

Re: The Diode [Post Homework Here]

Posted: Tue Dec 04, 2012 6:06 am
by ThePyroElectro
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.

Re: #6 The Diode [Post Homework Here]

Posted: Wed Feb 06, 2013 12:04 am
by jonnyquin
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:
http://www.google.es/url?sa=i&rct=j&q=& ... 4878062658
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

Re: #6 The Diode [Post Homework Here]

Posted: Wed Feb 06, 2013 10:37 pm
by ThePyroElectro
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:
http://www.google.es/url?sa=i&rct=j&q=& ... 4878062658
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


All your answers are correct. Good work!

Re: #6 The Diode [Post Homework Here]

Posted: Mon Oct 27, 2014 10:23 pm
by JohnOO
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?

Re: #6 The Diode [Post Homework Here]

Posted: Sun Nov 02, 2014 11:43 pm
by ThePyroElectro
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.

Re: #6 The Diode [Post Homework Here]

Posted: Mon Nov 03, 2014 8:19 pm
by JohnOO
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! :D
With possibility [2], I turned the trim pot partly towards 0Ω, and the LED died. Oh well, probably made a silly mistake without realising.
Thanks for the advice on buying bulk amounts of them, have already done so.