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Building a power supply for a Raspberry Pi 4 but having trouble with the output voltage of regulator

You are using a linear regulator (type of regulators, not the manufacturer). For a 3A output these require 3A input. And that means to have 15W output, it requires 36W in, and dissipate the remaining ...
Justme's user avatar
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Inconsistent resistance measurement in H-bridge

My hypothesis is that your transistors are slightly mismatched. The beta (hfe) on transistors can range between 30 and 400, which affects the effective emitter resistance. I've simulated the scenario: ...
user55924's user avatar
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Is 74244 buffer suitable for multiplying data and enable in my Rasberry Pi3 to ATmega128A bidirectional communication?

I don't see any advantage to an individual driver for each "data MAX485". Instead, let the ATMega drive two drivers for data, each driving 10 differential drivers, and two more drivers for ...
greybeard's user avatar
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Is 74244 buffer suitable for multiplying data and enable in my Rasberry Pi3 to ATmega128A bidirectional communication?

1. Using 74244 buffer is suitable for multiplying Raspberry data steam and enable signal 20 times for 20 groups of bus as in the diagram. Probably not. I'll be surprised if a RPi3 pin can drive that ...
Dave Tweed's user avatar
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Read multiple PT100 sensors with MAX31865

Use a MAX4782 dual MUX and remove track on 31865, like in this thread from the Arduino forum: https://forum.arduino.cc/t/max31865-pt100/612663/28
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Three wire remote controller - wiring to two GPIO pins

You can easily do it like this: (Note, I'm assuming you intend to hook up the remote trigger to the Pi, not the camera. DO NOT wire the camera to the Pi in the way I've drawn!) simulate this circuit &...
TypeIA's user avatar
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Three wire remote controller - wiring to two GPIO pins

You are risking damage to an expensive camera. To do this successfully requires some understanding of the camera's control logic, the maximum voltage the logic inputs can tolerate, the logic ...
Transistor's user avatar
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What are PIO asm pindirs and how do they work?

This technique is not specific to the RP4020, so is described generically. In brief The direction register is selecting between a high when dir is out (caused by 1 in the data output register) or a ...
jonathanjo's user avatar
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Can I use one 12 V 8 A power supply to provide 5 V 10.5 A power via buck converters?

That will work just fine. The buck converters will need to be at least 52.5/96 = 54.7% efficient, which is such a low requirement that practically any buck converter on the planet can do it. The Pi 4B ...
Jonathan S.'s user avatar
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Battery considerations for robot hardware

Analyse the actual cause of the problem with a scope. Until you do that everything is speculation and guesswork. Look at the supply going to the uC first and get a capture of the supply rail dip when ...
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Battery considerations for robot hardware

Answering one point regarding battery packs: I've had several battery packs with dual outputs. All have allowed both to be used at once. This may or may not help in your case, depending on how much ...
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Battery considerations for robot hardware

Add there a diode before dc-dc converters. High current to motors is sucking out the energy from the dc-dc input capacitors. And if it's not enouh add there more input capacitance to dc-dc converters.
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