I'm working on a project using several solenoids that operate independently and often need to be sustained in the "on" position. Each solenoid requires 5V input and draws 800 mA of current.
I'm looking for a driver chip to cut down the amount of wiring required for this circuit. I first considered a Darlington array chip, but these do not have a heat sink. Are there any alternatives to soldering a MOSFET/Diode pair for each solenoid?
You can use a MOSFET with the appropriate avalanche rating and the diode is not needed. You can also use a solenoid driver IC. Here is a link to TI's parts. Solenoid drivers product selection | TI.com
How many is "several" to you.
These modules can drive five solenoids each.
They also come in single units.
Leo..
You unsolder the terminal, connect the wires and solder it again.
...or break the modules apart. I believe putting them back together will not be an option 
Yes, I think they are meant to be broken apart, but I don't see much of a V-cut break line.
I did order once buck converters that came in a strip of five, but there was a clear break line.
What is hard to believe is the price difference between this lot and a single one.
Leo..
About a dozen. That seller doesn't ship to North America and seems to be misleading. Each of those chips (2 pairs of terminals) supports 1 solenoid.
Correct me if I'm wrong, but doesn't TI expect you to buy 1000 of that part for that price?
While we are here, lets see if the solenoids you chose are rated for continuous duty.
I'm using the Adafruit Medium Solenoid in what is likely to be a 5W capacity with a PWM signal. I need more stroke than force and found this to be the best option at the time.
That will not be a sustained on position, as the title states.
I am not sure but you can buy as few as 1 from one of the franchised distributes.
Those are facing correctly. The picture is showing 5 breakaway boards. Breaking them will of course require more mounting devices but that is easier then trying to rotate terminals that are not spaced for that. And yes I have used them and they do work.
Hi,
If you used MOSFET switching and PWM, and do some experimenting.
You should be able to find by reducing the PWM duty cycle, the minimum duty needed to consistently HOLD the solenoid active.
Usually they can hold on less energy than the actual activation energy.
So you use 100% duty to pull the solenoid in, then throttle back the PWM duty to a lower level that still gives the solenoid enough force to stay in position, but with lower power dissipation.
Good for the power supply and good for the solenoid windings.
Just a thought..
Tom.. 
I'm a bit new to this and just thought that was the best way to describe it. Not sure if "sustained on" is equivalent to "continuous duty" though.
Is there a better solenoid option for consumer use?
What is sustained? 10 seconds, 1 minute, 10 minutes, 10 hours?
To me that is indicating 24/7/365 or always on. But also realize that is a subjective term with no definitive answer.
Really hard to answer such a vague question. Consumer use may mean use once and toss, or it may mean it gets used once every time you fly your airplane.
About 50% of the time for a 10 minute period.
Off otherwise.
