EMRFD Message Archive 4303
Message Date From Subject 4303 2010-02-20 08:43:27 Brooke Clarke Understanding Mixer Diodes Hi Joe:
Schottky diodes can be made using different substrate materials and
different metals resulting in different performance in mixers. An easy
test for barrier height is to use the diode function (Vf @ 1 ma) on a
DMM like the Fluke 87 or similar, see: http://www.prc68.com/I/DMM.shtml
The lower the Vf @ 1 ma the lower the LO power needed for the mixer.
A more complex parameter is related to what's called space charge
current limiting and for that see:
Understanding Diodes & RF/Microwave Operation and points out that the WJ
app notes on mixers did not understand this.
http://www.prc68.com/I/Diodes.html
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Have Fun,
Brooke Clarke, N6GCE
http://www.PRC68.com