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About LinkBacksAnyone out there that can knock me together/link to a diagramfor a circuit that takes latches a pushbutton switch? Im wanting to set my reset button up as my on off switch for my case fans.
Anyone out there that can knock me together/link to a diagramfor a circuit that takes latches a pushbutton switch? Im wanting to set my reset button up as my on off switch for my case fans.
you still need this dude?
The easyest way would be to use a "LOGIC GATE" TTL type, her basic idea is an OR logic gate with the output connected to one of the inputs, an OR gate outputs high, when ever one or more of the inputs is high. So when first activiated the output would be low, but as soon as an input goes high, the output does, which is connected to the input, thus latching high.
A better way would be to use a latch... such as a 74LS279. If you want to shop at maplin a 259 could be used instead, but has to be "addressed" in binary, rather than simple parrallel line.
from farnell your looking at about 30p for a QUAD latch, that is 4 latches in one packet.
But as your driving fans, you'd need a high power transistor on the end.
But as your driving fans you might want to use a latching relay.
throw new ArgumentException (String, String, Exception)
Nah, ive since mved to some low power fans, so theyre just running off a mobo header. Latching relas is easy enough, but dont you then need one switch to latch on and another to knock it off?
Yeah a latching relay requires a set and reset switch. You can use a circuit like the following for a one-button on/off setup:
Thats exactly what i was looking for, id had that dia before, but i couldnt remember where i found it.
the FET is actually a better solution than what i was thinking, also as theres little voltage drop over a FET less power is disapated, comparied to a bi-polar transistor, which is what i was thinking (for some reason!).
to use a latching really you also need a transistor, or another realy to use one button.
If you want to control a bunch of fans on their own independant buttons, i'd recomend using a quad latch to drive a transistor.
throw new ArgumentException (String, String, Exception)
The only thing itd get used for now is lights, when i eventualy get them wired up, the plan is to use the reset switch to knock them on and off.
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