So it never occured to me that there existed ginormous op-amps that are capable of driving motors since all I have ever seen are the little IC things that amplify mA signals. I was looking at a link for a motor controller IC that someone asked about on the forum and their example circuit and it just had this measly little op-amp on the circuit driving what I assumed to be a motor. So I looked up this op-amp and it was huge! 10A! And then I looked into it more and found humongous 50A+ op-amps. I guess it never occured to me that people would scale up the op-amps I normally see to do these things.
I also found switching amplifiers which were pretty basic (just an H-bridge with drivers all mounted into one nice neat package)- those I understand. But I didn't know they had "linear" op-amplifiers that handled currents so high. Don't they dissipate tons of heat? Or do I need to brush up on my transistor knowledge?
I don't work with audio or anything like that- just robotics so I assume I would have run into these much sooner if I did. I guess they're just called "amplifiers" now instead of op-amps. I guess you would need them in things like really big speakers where you can't just switch on and off a transistor really fast...lol...Well I guess that's what a switching amplifier is isn't it? I guess there was a time when it was all analog and linear and not so much high frequency switching. I can't quite understand how a switching a signal on and off really fast can make something like DVD-quality sound though, but there's probably more to the system than that and some inductiveness going on to average out the voltage like in a motor, or some other mechanism. EDIT: Low-pass filter is the word I'm looking for.
But using an op-amp to drive a motor <-----blows my mind
I didn't know that switching amplifiers (well I didn't even know such things existed, or at least were considered amplifiers) were basically glorified H-bridges.
They don't seem to be cheap though. Well at least the ones from Apex are each $500+ even from the 150mA ones to the 50A op-amps or "linear amplifiers". Then again, the 150mA can run at 900V which is something you don't see in little IC op-amps. Still, expensive. The PWM amplifiers also cost the same. I could do the same thing for $20 with some transistors but it would probably only work for something like motors and not something where signal quality is needed like audio.
I also found switching amplifiers which were pretty basic (just an H-bridge with drivers all mounted into one nice neat package)- those I understand. But I didn't know they had "linear" op-amplifiers that handled currents so high. Don't they dissipate tons of heat? Or do I need to brush up on my transistor knowledge?
I don't work with audio or anything like that- just robotics so I assume I would have run into these much sooner if I did. I guess they're just called "amplifiers" now instead of op-amps. I guess you would need them in things like really big speakers where you can't just switch on and off a transistor really fast...lol...Well I guess that's what a switching amplifier is isn't it? I guess there was a time when it was all analog and linear and not so much high frequency switching. I can't quite understand how a switching a signal on and off really fast can make something like DVD-quality sound though, but there's probably more to the system than that and some inductiveness going on to average out the voltage like in a motor, or some other mechanism. EDIT: Low-pass filter is the word I'm looking for.
But using an op-amp to drive a motor <-----blows my mind
I didn't know that switching amplifiers (well I didn't even know such things existed, or at least were considered amplifiers) were basically glorified H-bridges.
They don't seem to be cheap though. Well at least the ones from Apex are each $500+ even from the 150mA ones to the 50A op-amps or "linear amplifiers". Then again, the 150mA can run at 900V which is something you don't see in little IC op-amps. Still, expensive. The PWM amplifiers also cost the same. I could do the same thing for $20 with some transistors but it would probably only work for something like motors and not something where signal quality is needed like audio.
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