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Not the easiest project you could find. From my point of viwew it should be as follows: use an unipolar stepper motor driver with a chopper. Complementary motor phases can be grouped, so you need only one current sense resistor for each pair, total two current sense resistors. The driver has to accept ABCD input sequence, not a step/dir interface The hall ...

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When you use a BJT as a simple switch (and assume that it will always be saturated when on) the rules are very simple: Assume an hfe less than the minimum in the datasheet. In the data you showed, you could assume an hfe of say 10 which makes calculations very easy. Divide your target Ic by your assumed hfe to find the base current required. Look up your ...

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Oooh I might be able to answer this (am a mechanical engineer by education). The BE junction doesn't "turn on" until you forward bias it, and as a "diode" you need 0.6V to forward bias, as a thumbrule. Once it turns on, it dumps current as necessary to maintain that 0.6V bias voltage, so you get zero BE current until you hit 0.6V, at which point current ...

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BJT's as switches aren't complicated. One input is the value of your power supply voltage -- call it $V_\text{CC}$. Another input is the desired operating current of the LED -- call it $I_\text{LED}$. Another input is the worst-case voltage drop of that LED when running at that desired operating current -- call it $V_{\text{LED}_\text{MAX}}$. Another ...

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LCD modules like that nearly never actually specify the initialisation vector in the datasheet, in part because the silicon vendor and the LCD vendor are not the same company. At best you can usually get the module vendor to give you some example code to base your routine on, but how to control the details like say gamma curves and such is pretty much a ...

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The series electrolytic capacitor is not a "load" — it simply serves to block DC while passing the huge bandwidth required for video signals in general. In general, the order of components in series doesn't matter, but in some cases, specific ICs might be sensitive to 2nd-order (parasitic) effects. This is the reason for the note on the THS7374.1 You ...

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The order of RC is irrelevant if using SMD caps. If using THT caps then use R 1st to reduce path length for stray capacitance over a ground plane which has higher stray capacitance (lower impedance is good). The R value is always 75 and prevents the C value decreases slightly due to spectral range is higher for Chroma.

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Brief: You may have connection issues. Driving strings arranged 2S2P may work. Drive ONE string of four at minimum acceptable brightness Measure and advise Vstring and I string. ________________________________________ Detail: The old driver will not light the whole string. You need to explain what this means. If you means that it lights part of ...

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Quite the old topic, but one important thing is missing : Half bridge voltage may force you NOT to use charge pumps. There is no practical charge pumps that allow to supply 20V to a high side switch with 400V ground offset. Charge pumps are more of a low voltage thing (I've seen them up to 60V bus voltage with few tricks to avoid reverse currents) but ...

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If you assume that the opamp is a rail-to-rail device you can then say from inspection: The configuration has unity gain. At zero load current the output limits at approximately +/- 4.3V (one V(be) drop from each supply). The configuration will clip at approximately +/-70mA and the output voltage will reduce linearly (the 10 Ohm resistor) above that current....

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All op-amps "try" to set 0V between its + and - terminals, so connecting the output directly for feedback should make it a voltage follower or buffer (amplifier with gain 1, Vo=Vi). The push-pull part made by the two BJTs is just for power output.

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