5 Solenoid (@3 AMP, 24 VDC) control from Stamp
Happy Dude
Posts: 9
Hi All,
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I am glad that I found this forum, hope somebody will·help this newbie. My problem is -
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I need to control·5 solenoids (drawing 3 AMP at 24 VDC) independently through stamp and wondering if I should use one MOSFET circuit for each solenoid or is there a MOSFET array type of chip which will simplify my circuit
·
Thanks,
Happy_dude
·
·
·
I am glad that I found this forum, hope somebody will·help this newbie. My problem is -
·
I need to control·5 solenoids (drawing 3 AMP at 24 VDC) independently through stamp and wondering if I should use one MOSFET circuit for each solenoid or is there a MOSFET array type of chip which will simplify my circuit
·
Thanks,
Happy_dude
·
·
Comments
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·· There may very well be a single-chip solution to what you are looking for, but I somehow doubt it due to power dissipation.· The IRL520 is a 9A+ MOSFET which would work in this application as long as each solenoid had a 1N4007 or similar diode to protect against back EMF.· These could be controlled directly from a BASIC Stamp.· Take care.
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Chris Savage
Parallax Tech Support
I think I will go with· IRL520 solution.
Is the coil drawing 3 amps, or are you running 3 amps across the contacts?
If the max coil amperage is <500mA then you can get a ULN2803A Darlington Array for under a dollar. This chip is a "power driver" with eight channels. You can run devices up to 30VDC @ 1/2 Amp across the E/C with a simple sinking (preferred) or sourcing 5 volt ttl output from the BS2.
Parallax has them.
Tommy
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(Frequently heard from other's)
Tommy, I know it wasn't designed to·x, but can you make it·do x·anyway?
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·· Since he specified Solenoids I’m not sure what you mean about contacts, but I did want to make you aware of something when using the ULN2803.· Many people take that 500 mA rating per channel too literally.· Once you get more than one channel going that number goes down since there is a more important rating called, “Total Power Dissipation”.· The most current I have heard being drawn from each channel when all were in use is ~350 mA and I believe that was under ideal circumstances.· Take care.
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Chris Savage
Parallax Tech Support
I read solenoid, I hear coil.
TT
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(Frequently heard from other's)
Tommy, I know it wasn't designed to·x, but can you make it·do x·anyway?
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·· No doubt a solenoid and a relay are basically identical from an electronic stand-point.· In fact I usually use a relay driver schematic when demonstrating driving a solenoid (see attached).· I just wanted to make sure we were all on the same page since, on a relay the coil current is a lot less than a typical solenoid.·
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Chris Savage
Parallax Tech Support