So I dropped into my local part store and was told that these darlingtons could run some motors, although when I read the datasheet on them they seem overpowered at 60v, however they can aceept currents up to 2A. Are these minimum values or do them have to be close to if not matching 60v?
datasheet here http://www.datasheetcatalog.org/datasheet/stmicroelectronics/4126.pdf
Do not know about the
Do not know about the electronics… But I do now that you cannot reverse current with any Darlington I have learned to know. And so your robot will have a hard time once it finds a wall, the ceiling, earth, bottom of the lake, or outer space (depending on what it does)
(You cannot reverse)
A few quesstions
A few quesstions first:
What are your plans?
it helps to answer correctly when you describe how you’ll be using these - darlington offer an impressive current capacity, but cant be used in parallel like mosfets
What is voltage is your system running?
100v?
What are the specs of the motors?
1 Amp motors?
How are the motors going to be used?
What loads do you expect - intermittent use - or will the short at any time - e.g. shaft stops for mechanical reasons, current can race through the motor & controller
for more info on darlington specifics - there is always wikipedia
Huh?An H bridge built with
Huh?
An H bridge built with darlingtons will reverse current…
Or am I completely missing something? Wouldn’t be the first time… (Fritsy has seen my fried circuits)
BLUE smoke
H bridge will work. Just make sure your logic doesn’t allow both “high sides” or both “low sides” to be energised, or you will get “shoot-through” and all the blue smoke will come out. As you know, it’s the blue smoke which makes transistors work. It’s a very skilled task to put the smoke back in, so the chances are once it comes out you need to put the trannys in file #13 (that means the bin).
One thing you can do is PWM the two low side switches and cause the high side switches to be energised by the current flowing out of the “other” side of the motor.
Facts sheet schmacts shet
I haven’t looked at the facts sheet, but I’d say these are maximums. YOu don’t have to approach the 60V for it to work. Just for reference, the 60V has NOTHING to do with the power (“overpowered” you said) rating of the transistor.
