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6 answers
Why does hardware division take much longer than multiplication?
Why does hardware division take so much longer than multiplication on a microcontroller? E.g., on a dsPIC, a division takes 19 cycles, while multiplication takes only one clock cycle.
I went through some tutorials, including Division algorithm and…
Marko Gulin
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45
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6 answers
What is electrical insulation tape officially for?
Seemingly obvious question, but. There are electrical supply companies that sell insulation tape in boxes of 12 or 24 units. Seems that there's quite a demand for the stuff.
No commercial product I've ever seen uses insulation tape. They use…
Paul Uszak
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45
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5 answers
Is there an ideal PWM frequency for DC brush motors?
I'll be using a microcontroller to create a PWM signal for motor control. I understand how PWM and duty cycle works, however I am unsure about an ideal frequency. I do not have my motor in yet, so I can't just test it and find out.
The picture…
Nate San
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45
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4 answers
What does edge triggered and level triggered mean?
I am studying 8085 microprocessor architecture and the terms edge triggered and level triggered confusing me really very much. Can anyone explain me it in layman's words ?
While studying the interrupts of 8085 named RST 7.5, RST 6.5, RST 5.5 and…
Ankur Trapasiya
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45
votes
5 answers
Why do ICs have NC (No Connection or No Function) pins?
In case they have no use to the end users and have no function, why are they given as pins instead of being just closed? Some ICs have even 4-5 NC continuously (in accordance to their pin number).
Ajith Natarajan
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45
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3 answers
Switching DC with MOSFET: p-Channel or n-Channel; Low Side Load or High Side Load?
I think, it is time I understand working principle of MOSFET transistors...
Suppose that;
I want to switch voltage on a resistive load by a MOSFET transistor.
Any control signal between -500V and +500V can be easily generated.
The transistor…
hkBattousai
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45
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3 answers
Basic transistor questions
I've created the circuit shown. I'm using a 9V battery (actually throwing out 9.53V) and 5V coming from an Arduino to test with both 9 and 5 volts. The transistor is a BC 548B (datasheet I'm using is here).
simulate this circuit – Schematic created…
hojkoff
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votes
8 answers
Why isn't there a potential difference across a disconnected diode?
I know this question sounds silly, as if there was a potential difference a current would be created when the terminals are connected together and this would mean energy has come from somewhere.
The reason I ask this though is that from my…
Blue7
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44
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3 answers
Why don't typical digital multimeters measure inductance?
Even with predominantly digital circuits, I am using inductors much more often than I used to, generally because of all the buck or boost converters (a recent board I was involved in has 12 different voltage rails -- six of them needed just by the…
tcrosley
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44
votes
1 answer
Step up 3.3V to 5V for digital I/O
I normally use an Arduino for my projects because it has 5V inputs and outputs and has 5V Vin so that makes life very easy when interfacing with 5V components. For this project I want to use a Raspberry Pi because I want to hook it up to a display.…
Huckle
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44
votes
2 answers
Sharp corners in PCB traces
Why does a typical PCB always has rounded tracks? What harm can a sharp edged PCB track can cause? Please explain!
Vinit Shandilya
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44
votes
3 answers
what is the difference between PHY and MAC chip
I want to know what is the difference between PHY and MAC chip
user152250
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44
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7 answers
How does an antenna radiate (how do currents flow through the wire)
I don't understand how antennas radiate a signal.
I understand the basics of antennas (wavelength, electron E field, etc.), but I simply don't understand how a current can go through a wire that doesn't have negative pole.
Can you please explain…
depecheSoul
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44
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2 answers
44
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5 answers
Why did Axial Capacitors Fall Out of Use in the Industry?
When inspecting the boards from electronics made in 1980s and earlier, one distinct feature is the extensive use of axial, electrolytic capacitors as power supply filter. Axial ceramic decoupling capacitors were used as well, to a lesser extent.…
比尔盖子
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