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5

Both your circuits suffer from shoot-through issues. This is what happens when you do not give each transistor an independent control signal. The problem is may be worse in your top circuit since the high-side gate driver is much more effective than the low-side gate driver. On the other hand, I don't know what R4 and R12 are supposed to be for since they ...


2

So after many hours of testing, and rebuilding it all on a breadboard I think I found my mysterious issue. Seems that my reflow oven is the culprit. The data sheet specifies that the leads should not exceed 300℃ for longer than 10 seconds. It doesn't appear to heat up the board that high during the reflow process. But hand soldering the chip on by hand at a ...


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In a switching converter this is desirable because it means that it lets the current in the inductor never fall to zero which lets you run in continuous mode instead of discontinuous mode which produces less ripple and noise (I think...it's something like that). In a motor this is desirable because you don't throw away all the energy put into building up ...


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You typically choose a PWM frequency high enough to limit the ripple in the current through the motor to prevent torque oscillation and audible noise, and so the current during the off period won't decay to zero except at very low duty cycles. At 50% duty cycle, the motor will be running at about half full speed, and the current through the freewheeling ...


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If anyone wants to know about diagram then here it is. I draw it . And I like to share it with you guys. Mx1508 diagram.


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It's probably something like this that you are after.... When this type of circuit is used for a bridge connected class AB audio amplifier (swap motor for speaker) it is important to reduce crossover distortion as much as possible by using both techniques of feedback and biasing the transistors slightly on with the diodes. Without the diodes, (bases ...


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you gotta start with better specs in case you hadn’t noticed yet, your BJT’s are always conducting creating a condition called ‘shoot thru’ , shorting out the supply on both sides. There must always be a dead band and thus a deadtime during transition. start with your output impedance model of a motor with back EMF as a motor/generator or simply ...


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You aren't going to get anything below 0V if your low supply Vee is at ground and not -30V. Swing around 0 can only happen through a transistor stage if total voltage from collector supply to negative supply is bounded greater than your desired swing. This is why your output stage is automatically biasing to a a +-15V swing around +15V. Also, an AB output ...


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You are asking for trouble; the drive frequency is 140 kHz and your primary series resonant tuning is precisely 140 kHz therefore, the L and C act as a short circuit at the switching frequency. You need to run the primary circuit either from an output stage designed to handle the series resonance or use a different approach - maybe add a current limit ...


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It appears to be a high voltage controlled power tool used as an engraver. These often have diamond tips. There is a current limiter of 2.1A on 24Vdc and a FET complementary drive to a centre-tapped boost transformer. Thus it draws less than 50W. PWM control is a guess, although it could be frequency control for resonance. Piezo is just a guess too. The ...


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