Need 5VDC 100mA to 12VDC 1A converter

Hi Mike I think you are missing one thing. It only takes the 12V to actuate the solenoid. The voltage and current can be quit a bit less to actually hold it open once it is actuated. Look at setting up, for experimenting, a large cap with a series resistor to something like 20VDC. Place a 1 amp diode in series with a low voltage supply that you'll use to hold the coil. Experiment with different holding and charging voltages. You may find that it is not all that impractical after all. Dwight

Reply to
dwight elvey
Loading thread data ...

On my other suggestion, did you look at possibly using Latching solenoids?

Reply to
Tony

: >> You have USB? Why didn't you say before? In that case you have a PC : >> nearby and chances are that it contains a fairly beefy 12V power : >> supply. : >

: > ... which is probably plugged into an outlet which is likely to be readily : > stepped down to 12v @ 1a. : >

: > But I have a feeling this person knows this, but since they didn't tell us : > everything about the task at hand all we can do is take shots in the dark.

: That sure wasn't my intention! The USB spec allows for 100mA, if I am : reading it right, unless one has a powered hub. My circutry is all cmos and : draws just a few hundred microamps, if that.

It depends if you are at the root controller or at a hub and if the hub is self-powered or bus powered. 100 mA is a unit load, but 500 mA should be available from the usb root or a self powered hub.

Bye

--
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
 Click to see the full signature
Reply to
Uwe Bonnes

I can't require that users use a self-powered hub because it will be perceived as an additional cost and complexity to my system.

I'm still on the learning curve with USB and I'm not sure what you mean by usb root.

Thanks,

Mike

Reply to
Mike Turco

"dwight elvey" wrote

Hi Dwight,

The voltage isn't as much an issue as the current, however, I've noticed that the actuation voltage is not that much higher than the hold voltage.

I've done quite a bit of experimentation with this solenoid already. It will not hold reliably without >350mA (or something like that).

The opening of the solenoid is so quick, I can't see the current on a digital meter. It didn't make sense to bother with a big setup for measuring that initial spike, once I saw that the hold current requirements were so far out of line with my what I had hoped to see.

I'll play around with the solenoid some more. Really, I'd like to replace the whole latching mechanism. I've gotten some interesting ideas from other portions of this thread.

Mike

Reply to
Mike Turco

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.