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Motors are like capacitors, you can't use a single resistor to reduce the voltage on a capacitor, likewise a single resistor won't work well to reduce the voltage to a motor. you could use two resistors to make a divider and have more success slowing the motor. the resistors will make lots of heat, but maybe you can use the heat for something. getting less ...


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The speed of DC motors depends on voltage, the current is proportional to the torque. If your mechanical load is very low, you will have low current, and the voltage drop in a resistor will be also low, so no change in speed. You can try with diodes, if the current is not very low, you will get moreless 0.5 volts with each one. Other trial should be to use a ...


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Is there some other way to work out the switching frequency or choose those capacitor values? The UC3842 data sheet shows this graph: - RT and CT in your diagram are here: - So, remove C106 and test it with a capacitance meter because there's no other way to determine the switching frequency given that the device may be damaged. You might get lucky by ...


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As the resistive divider (or potmeter) is an important part of the feedback in this regulator, you cannot simply remove/replace it with something else as that would influence the feedback loop and the output voltage would not be regulated anymore. What is possible however is that pulling/pushing a DC current into the voltage divider at the point that is ...


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What others said, plus ... I would LOWER the gate voltage to in the 12-15V region. Data sheet graphs suggest that this should be more than adequate (even allowing for them being "typical" curves" and this gives you more headroom between Vgs and Vgs_abs_max for transients. Place a reverse biased zener between gate and source, as close to FET ...


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Three things (and a last thing edit): Make sure the gate rise times and fall times are as short as possible Make sure the gate voltage is above 10V minimum and rdson is low Make sure the mosfet has good thermal dissipation It's most likely thermal death that killed the mosfet. This happens when the gate is brought low or brought high because momentarily ...


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The main problem is that you haven't designed a level translator: - It's a source follower and the voltage at the source will be approximately what is at the gate but about a volt lower in amplitude (MOSFET depending). It won't give a 5 volt PWM level translation. To do that you need the source connected to ground and a resistor from drain to 5 volts. This ...


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It's hard to say since we don't know what the input to the WS2812B is, but the datasheet does say that the digital input should be between -0.5V and 5.5V (which typically means there is diodes on the output and the input current is 1uA, which typically means that it is a FET not a BJT transistor input. If the signal were to exceed 5.5V it would turn the ...


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Yes, you really do need a differential PWM signal if you want to use the differential pins (inputs 3-10) on the CGD1200HB2P-BM2. The Threshold voltage is shown in the Gate Driver Electrical Characterization: You need to have a differential voltage below -200mV and above -7V in order for the 0 to be detected.


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To answer your specific questions for this task: MOSFET - Pros: None Cons: High gate capacitance could lead to low switching speeds. Optocoupler - Pros: Electrical isolation Cons: Multiple components 4.7k Pull Up - Pros: Low cost and easy Cons: Only applicable if MCU has 5V tolerant inputs You could also try option number 4: Use a discrete logic IC for ...


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That looks very much like a problem with the compensation adjustment on your probes. Your scope should have a calibration signal output. Check that your scope shows a nice square wave when the probe is connected to the calibration output. If the calibrstion output doesn't look nice and square with straight, vertical edges and flat, horizontal tops and ...


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No. I mean: you can apply a PWM pulse on the enable pin, but it can interfere with the internal chopping frequency used by the Allegro A4988. I've tested your idea with different duty-cycles offered by an Arduino (PWM = 490 Hz - IIRC) and it was not working at all: the movement of the stepper was erratic and not regular. Unusable. The only duty-cycle values ...


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PWM can regulate current with current sensing across a sense resistor. The CC source uses PWM with an inductor and Cap with compensation for stability in the closed loop. It is intended for each color as a DCDC converter with 95% efficiency, not shared. If you want to vary brightness then current must be modulated.


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A constant current source is a voltage source with a feedback loop that regulates current. The purpose is to avoid the current limiting resistors that waste energy and/or provide more precise control of brightness without needing PWM. You've designed a circuit that adds the PWM and current limiting resistors back in, in which case using the constant ...


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That controls the width of the PWM pulse according to the formula: pulse_length = ((TIM_Period + 1) * DutyCycle) / 100 - 1 You use that to calculate the desired duty cycle. While you can set that in STM32CUBE IDE, you most often set it from your program as you vary the PWM for whatever you are doing at the time. Usually you will set it to 0 in the IDE as an ...


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how to cut the strips then Where the label says ;) Standard 12V LED strips use series strings of LEDs. Since the Vf of a white LED is a little bit above 3V, they simply wire 3 LEDs in series which makes a bit more than 9V. A current setting resistor is added to each series string to soak up the extra voltage. 24V strips use the same arrangement with 6 or 7 ...


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The WS28xx series leds have an ic in them to do the PWM and the protocol. Therefore it is not unreasonable that the 12V ones (and the 5V ones for that matter) manipulate the PWM such that the LEDs themselves don't get damaged. One thing to note with LEDs is that the current has to be limited, not the voltage but the voltage has to be sufficient in order to ...


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One solution, which more experienced people would hesitate to suggest because it perpetrates the dead-end practice of using delays, but it's close to what you already have, is to modify slightly the single thread you have, to update all three phases. Use a phase increment of 120+delta (degrees) DELTA = 10 # degrees SOME_TIME = 1.67 ms - processing_time # ...


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You don't do it that way. You have a function to calculate the sine function based on the time. All you do is add your delay to the time. D is the time difference between the phases. t is the current time Phase 1 is sin(t) Phase 2 is sin(t+D) Phase 3 is sin(t+2D)


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To keep the high-side FETs turned on their Gates need to go above the battery voltage by >=10 V. However you must also ensure that they don't receive more than 20 V between Gate and Source, so you can't just boost the battery voltage by 10 V because then the total would be 22 V which could blow up the FETs. One way to do it is with an isolated DC/DC ...


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To solve this problem you can connect the Arduino to power supply so the ground of the Arduino will not be broken with the scope


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when the signal is connected to the input of the gate driver IC (IR2104) the low side driver output shows the signal with the compliment of the duty cycle (1-D)? why? That's what this chip produces: -


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The datasheet shows on page 4, under "lead defintions": IN: Logic input for high and low side gate driver outputs (HO and LO), in phase with HO In addition, the functional block diagram shows the input for the low side driver being inverted. Thus, when IN is high, the top side MOSFET is on and the bottom one is off.


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