Diodes
Diodes continued
Zener Diode
Zener Diode Table
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ZENER DIODE
A zener diode works in reverse biased region. In reverse biase
it gives fixed output voltage. The following diagram shows a normal
connection for the zener diode. The current limiting resisting
should be chosen properly. Let's take an example
for the use of zener diode, USB port gives Vcc=5V,
but it takes input voltages around 3.3V. So we
apply this circuit with zener diode,Vz=3.3V, (because most
embedded systems work at 5V) to get voltage=3.3V. In forward bias
it works as a normal diode.See the link
http://www.allaboutcircuits.com/vol_3/chpt_3/9.html
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/zener.html
http://www.phys.ualberta.ca/~gingrich/phys395/notes/node60.html
NOTE: If current limit resistor is
not connected or it is not of proper value, then it
cause heating of the zener diode. So remember about this before
touching zener diode.If the input voltage is less than Vz then
output voltage will be zero(ideally).
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