Hi Dan, Those are interesting little diodes. I can put a direct short in the circuit and they still limit it to 1 MA. I calculated it takes about 5.5 to 6 inches of 14 gauge wire to give the correct surface area for 1 ma current.
Take care, V Energize With Light http://www.theledman.net/ > I think "current limiting diodes" is something of a misnomer, kind of like > products marked > "unscented" which have scent in it, or like "Liberal" and "Conservative" in > the political realm... > By the way, don't buy the exact 1.0 ma diode, buy one tenth ma less than or > greater than (ie. 0.9 ma > or 2.1 ma). They are less than half the price of the exact 1/0 ma diodes. > Dan > IV.5 - Current Limiting diodes? > Constant current two-terminal devices can be made by shorting the gate and > the source of a JFET > together. When the FET is forward biased, this results in a nearly constant > current for voltages > ranging from roughly 2V up to 300V (or the breakdown voltage of the device in > question). In reverse > bias, this kind of constant current device conducts as a junction diode (so > one can oppose two such > devices in series to regulate AC current). > Siliconix makes two-lead FET current-limiting diodes ranging from 0.24 mA > (J500) through 4.7 mA > (J511) in plastic packages, and from 1.6 mA (CR160) through 4.7 mA (CR470) in > metal TO-18 packages. > National Semiconductor makes a three-terminal adjustable device, the > LM134/LM234/LM334, that acts as > a resistor-programmed current source diode, analogous to the > 'programmable Zener' TL431. Adjustment > range is 1.0 uA to 10 mA, and voltage compliance is from 1V to 40V (or 30V > for some versions). The > current is slightly temperature-dependent (this may be useful, or can be > eliminated with a diode > added to the adjustment resistor). -- -- The Silver List is a moderated forum for discussing Colloidal Silver. Instructions for unsubscribing are posted at: http://silverlist.org To post, address your message to: silver-list@eskimo.com Address Off-Topic messages to: silver-off-topic-l...@eskimo.com The Silver List and Off Topic List archives are currently down... List maintainer: Mike Devour <mdev...@eskimo.com>
