Difference between revisions of "Diode"

Latest revision as of 15:40, 4 December 2019

Key Stage 4

Meaning

The symbol for a diode.

A diode is an electrical component which only allows electricity through in one direction.

About Diodes

Diodes have a low resistance in one direction but a very high resistance in the reverse direction.

Diodes can be used to change an alternating current into a direct current.

IV Graph

Description

The IV Graph for a diode shows that:

For a positive potential difference the current increases rapidly with an increase in potential difference
For a negative potential difference the current remains negligible and does not increase as the potential difference becomes larger.

Explanation

The resistance of a diode is very low for current in the forward direction and very high in the back direction.

Obtaining the IV Graph

	Connect an ammeter in series with the diode to measure current through the diode. Connect a voltmeter in parallel with the diode to measure the potential difference across it. Use a variable resistor in series with the diode to vary the potential difference across the diode. Start with a potential difference of zero and increase the potential difference by an interval of 0.2V up to 2V. Recording the reading on the voltmeter and ammeter. Reverse the connections on the battery and repeat steps 4 and 5 to find the I-V relationship for negative potential difference and current.

References

@@ Line 7: / Line 7: @@
 : [[Diode]]s have a low [[Electrical Resistance|resistance]] in one direction but a very high [[Electrical Resistance|resistance]] in the reverse direction.
 : [[Diode]]s can be used to change an [[Alternating Current|alternating current]] into a [[Direct Current|direct current]].
+===IV Graph===
+{| class="wikitable"
+|[[File:IVGraphDiode.png|center|400px]]
+|}
+====Description====
+The [[IV Graph]] for a [[diode]] shows that:
+*For a positive [[Potential Difference|potential difference]] the [[Electrical Current|current]] increases rapidly with an increase in [[Potential Difference|potential difference]]
+*For a negative [[Potential Difference|potential difference]] the [[Electrical Current|current]] remains negligible and does not increase as the [[Potential Difference|potential difference]] becomes larger.
+====Explanation====
+: The [[Electrical Resistance|resistance]] of a [[diode]] is very low for [[Electrical Current|current]] in the forward direction and very high in the back direction.
+====Obtaining the IV Graph====
+{| class="wikitable"
+|-
+|[[File:DiodeIVGraphCircuit.png|center|300px]]
+| style="height:20px; width:300px; text-align:left;" |
+#Connect an [[ammeter]] in [[Series Circuit|series]] with the [[diode]] to measure [[Electrical Current|current]] through the [[diode]].
+#Connect a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[diode]] to measure the [[Potential Difference|potential difference]] across it.
+#Use a [[Variable Resistor|variable resistor]] in [[Series Circuit|series]] with the [[diode]] to vary the [[Potential Difference|potential difference]] across the [[diode]].
+#Start with a [[Potential Difference|potential difference]] of zero and increase the [[Potential Difference|potential difference]] by an interval of 0.2V up to 2V.
+#Recording the reading on the [[voltmeter]] and [[ammeter]].
+#Reverse the connections on the [[battery]] and repeat steps 4 and 5 to find the I-V relationship for negative [[Potential Difference|potential difference]] and [[Electrical Current|current]].
+|}
+===References===
+====AQA====
+:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Diode, pages 52-3, 65, GCSE Physics; Student Book, Collins, AQA '']
+:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Diodes, page 43, GCSE Physics, Hodder, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe09847 ''Diodes, pages 180, 181, 183, GCSE Combined Science; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac91 ''Diodes, pages 24, 26, GCSE Physics; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Diodes, pages 293, 298, GCSE Combined Science Trilogy 1, Hodder, AQA '']
+:[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Diodes, pages 52-53, 57, GCSE Physics; Third Edition, Oxford University Press, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Diodes, pages 60, 66, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Diodes, pages 62, 68, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Diodes; circuit symbol, page 38, GCSE Physics, Hodder, AQA '']
+====Edexcel====
+:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Diodes, page 148, GCSE Physics, Pearson Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Diodes, page 229, GCSE Physics, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Diodes, page 388, GCSE Combined Science, Pearson Edexcel '']
+====OCR====
+:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Diodes, pages 107, Gateway GCSE Physics, Oxford, OCR '']
+:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Diodes, pages 176, 179, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR  '']
+:[https://www.amazon.co.uk/gp/product/1782945687/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945687&linkCode=as2&tag=nrjc-21&linkId=9a598e52189317a20311d7a632747bc9 ''Diodes, pages 45-47, Gateway GCSE Physics; The Revision Guide, CGP, OCR  '']