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[[Reverse Protection Diodes]] (protects against reversed GND and +power)
 
[[Reverse Protection Diodes]] (protects against reversed GND and +power)
 
rectifier -- not only protects against reversed GND and +power, but also allows the device to work either way.
 
  
 
fuses
 
fuses
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* "Fundamentals of PolySwitch Overcurrent and Overtemperature Devices" http://www.circuitprotection.com/06Databook/fundamentals/PSWFundamentals.pdf
 
* "Fundamentals of PolySwitch Overcurrent and Overtemperature Devices" http://www.circuitprotection.com/06Databook/fundamentals/PSWFundamentals.pdf
 
* 4 page overview and selector guide http://www.circuitprotection.com/06Databook/PSWFundamentals(80-83).pdf
 
* 4 page overview and selector guide http://www.circuitprotection.com/06Databook/PSWFundamentals(80-83).pdf
 
Be careful with these devices, they have a long term failure mechanism which means that after some cycles they do not return to their low impedance state. I cycled a device for 1.1 million cycles and all seemed well. However we still get devices back from the field that have failed (6K at room temp rather than 10 ohms). I expect that some are more susceptible.
 
  
 
== Input Protection by Circuit Type ==
 
== Input Protection by Circuit Type ==
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=== Blocking Diode ===
 
=== Blocking Diode ===
  
=== Zener Diode ===
+
=== Zeener Diode ===
  
 
=== Crowbar Circuits ===
 
=== Crowbar Circuits ===
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== Further Reading ==
 
== Further Reading ==
  
* [[Printed Circuit Boards#References]] discusses EMC guidelines
 
 
* [http://www.ce-mag.com/99ARG/Bjorklof&Joha124.html CE magazine: "Immunity Testing: Practical Aspects of Basic Standards"] by Dag Björklöf and Lars-Olov Johansson
 
* [http://www.ce-mag.com/99ARG/Bjorklof&Joha124.html CE magazine: "Immunity Testing: Practical Aspects of Basic Standards"] by Dag Björklöf and Lars-Olov Johansson
* The "super reverse protection diode emulator" idea is detailed in [http://www.geofex.com/Article_Folders/mosswitch/mosswitch.htm "Advanced Power Switching and Polarity Protection for Effects"] and [http://www.irf.com/technical-info/designtp/dt94-8.pdf IRF: "Reverse battery protection with HEXFETs doubles battery life"]; a BJT version that works almost as well is described in [http://www.geofex.com/Article_Folders/cheapgoodprot.htm "A cheap - and good - polarity protector"].
 
* [http://electronics.stackexchange.com/questions/14609/reverse-polarity-protection-on-model-rc-aircraft "Reverse polarity protection on model RC aircraft"] discussion
 

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