| maxw |
I just thought I'd share the Soft-Power Circuit I made. Someone might find it handy and eagle files are attached so others can etch their own and change it to suit them. Its based on these two designs using a 4013 flip flop:
http://www.cpemma.co.uk/flipflop.html
http://maxhawk.flagshiphosting.com/...nonv2/index.htm
It basically just lets you use a nice little momentary switch to activate a relay for switching amps, preamps or whatever on and off, just like a bought one :)
Mine uses a transformer from Jaycar which is exactly like an Amveco one but it is 45mm square instead of 50mm. I will be using a solid state relay.
Pics:

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| maxw |
| I forgot to attach the eagle files. |
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| excetara2 |
| Thanks a lot. I might need that. Some good pictures by the way. |
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| Eva |
That's great, but a bit of an overkill. First, note that it can be done without the transformer if the on-off signal is allowed to be mains live. Second, the solid state relay may be replaced by a triac and triggered by a compact 8 pin microcontroller, that may also achieve other functions like phase controlled soft-start, brownout detection, frequency checking, overvoltage and undervoltage protection, emergency shutdown, etc...
That's how I would do it. |
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| maxw |
| quote: | Originally posted by Eva
That's how I would do it. |
Well, post up your schematic and PCB layout then :clown: |
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| Workhorse |
Have a look at this Soft-Start using IGBT.....
regards,
K a n w a r |
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| Bratislav |
| it looks like your IGBT might fire (sic) only once ;) |
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| sawreyrw |
Workhorse,
It won't work. You can't turn the IGBT on without a positive gate supply.
Rick |
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| maxw |
| quote: | | Originally posted by Eva First, note that it can be done without the transformer if the on-off signal is allowed to be mains live. |
Also, one of the main motivations for using my circuit is so that you can use nice looking switches on your equipment and most of them will not take 110/220V, eg the bulgin switches:
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| Workhorse |
Hi Rick,
If you look at the optocoupler, its actually a Photovoltaic Driver from IRF which upon LED activation in it produces a voltage for gate drive of IGBT by the virtue of Photocells arrayed in it......
So theres no need of external supply apart from triggering the LED which could simply powered up by small rectified voltage scale down from mains AC itself.....
Have a look at this:
http://www.irf.com/product-info/dat...s/data/pvin.pdf
K a n w a r |
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