hello, I understand for inductive loads that they are reverse EMF that is induced as a magnetic field collapses and this can damage transistors and other IC's, my question is if I hook a brushed dc motor up to 3.7v directly, do I need a flyback diode between my battery and motor?
Pics attached below( basically I took apart my facial hair trimmer and found a very small motor hooked up to a 1.5v AAA battery which works fine and obviously has not effected a dry cell AAA battery but would this be bad for higher voltage lipo (3.7)?
The back-EMF only occurs when power is disconnected so you might get an arc inside a switch or you could blow a transistor or MOSFET but it shouldn't hurt the battery.
But it's never "direct". That would be like having a car with only "D" on the transmission. You can never park the car as it's always driving forwards. You can't reverse either.
So there must be a switch or something. If you're just holding the wires on the battery with your fingers then you've made a switch which can disconnect the battery from the motor when you remove your fingers. Since it's disconnected, the motor can't do much to hurt the battery. Maybe if you drop the motor onto the battery: don't do that.
MorganS:
But it's never "direct". That would be like having a car with only "D" on the transmission. You can never park the car as it's always driving forwards. You can't reverse either.So there must be a switch or something. If you're just holding the wires on the battery with your fingers then you've made a switch which can disconnect the battery from the motor when you remove your fingers. Since it's disconnected, the motor can't do much to hurt the battery. Maybe if you drop the motor onto the battery: don't do that.
that makes sense, I wasn't sure if the reverse EMF could enter through the other battery terminal when I disconnect one terminal at a time but thank you for a response.
MorganS:
If you're just holding the wires on the battery with your fingers then you've made a switch which can disconnect the battery from the motor when you remove your fingers.
If you are touching the wires as you break the circuit you may get a shock - with a large motor or inductor this
is a potentially dangerous shock (but very short duration). Treat inductive loads as high voltage...
MarkT:
If you are touching the wires as you break the circuit you may get a shock - with a large motor or inductor this
is a potentially dangerous shock (but very short duration). Treat inductive loads as high voltage...
MarkT:
If you are touching the wires as you break the circuit you may get a shock - with a large motor or inductor this
is a potentially dangerous shock (but very short duration). Treat inductive loads as high voltage...
Thank you for that information.