Most Popular

1500 questions
64
votes
3 answers

How does my screen driver handle so much data?

I just did some quick calculations: On my MacBook I have a resolution of 2560x1440 multiplied by 24 Bit for colors we get 11.05MB for a single picture or 663MB per second at 60 fps. I guess there is some compression, but for example when I move with…
Felix Crazzolara
  • 698
  • 5
  • 14
64
votes
10 answers

Why is RAM not put on the CPU chip?

Modern CPUs are very fast compared to all things external, including memory (RAM). It is understandable, since CPU clock frequency has reached a point where it takes several clock ticks for an electric signal simply to run from from the CPU through…
Lesser Hedgehog
  • 751
  • 1
  • 6
  • 6
63
votes
7 answers

How are integrated circuits fabricated?

How are integrated circuits (e.g. a microprocessor) fabricated from start to finish? For example, there must be some wiring with resistors, capacitors to store energy (bits) in a field, transistors, etc.... How is this done? What machinery and…
Holly Jona
  • 673
  • 6
  • 3
63
votes
3 answers

Noise and what does V/√Hz actually mean?

Noise figures in (op-amp) datasheets are expressed in V/√Hz, but Where does this unit come from? Why the square root? How should I pronounce it? How should I interpret it? I know lower is better, but will a noise figure that doubles also double the…
jippie
  • 33,221
  • 16
  • 95
  • 161
63
votes
1 answer

What are these boxes mounted inline on each of the 3 phase wires of a high voltage power line in Miami?

They were only on this run and not any of the lines in the area. And what is the function of the flat u-shaped guards in front of each?
bigjosh
  • 10,088
  • 32
  • 52
62
votes
2 answers

"Remove After Washing" on Piezo Buzzer

Maybe this is a stupid question, but here goes: I just got a piezo buzzer and on the top there is a sticker that says "Remove After Washing". My question is why would I ever want to wash an electronic part? I have no idea. Is there some…
kmort
  • 882
  • 1
  • 7
  • 13
62
votes
3 answers

What is the latency of an LED?

LEDs are known to have a very low, unnoticeable power-cycling latency, but how fast are they when measured? (nanoseconds?) In other words, how long does it take for an LED which is entirely off to get to its optimum brightness, and how long does it…
ayane_m
  • 811
  • 1
  • 6
  • 13
62
votes
3 answers

Is this video fake? I thought Tesla coils only worked on AC

This video shows a 9-volt battery connected to a wire as a primary. The first reason I think this is fake is that he is powering a Tesla coil with 10 volts. The second reason is that Tesla coils work on AC, or at least I thought so, and he wouldn't…
Gabriel ashmore
  • 691
  • 4
  • 8
62
votes
8 answers

How do I go from an Arduino on a breadboard to creating a real device?

My first Arduino project: I have made a headlight sensor that will activate an outside light when a car's headlights hit it. I know I could go buy one, but where is the fun in that? Now I would like to make a "real" one to mount outside my house so…
Steve
  • 779
  • 1
  • 10
  • 15
62
votes
7 answers

Why are there teardrops on PCB pads?

What's the use of the teardrop shapes around some PCB pads?
Federico Russo
  • 9,688
  • 17
  • 69
  • 119
62
votes
5 answers

How can an FPGA outperform a CPU?

I hear of people using FPGAs to improve performance of systems that do things like bit-coin mining, electronic trading, and protein folding. How can an FPGA compete with a CPU on performance when the CPU is typically running at least an order of…
David Gardner
  • 1,583
  • 1
  • 13
  • 15
61
votes
6 answers

Why am I not dead after repeatedly touching a high-voltage source?

While playing with mosquito racket in my home, I unscrewed the racket and touched the 2 wires with my hands. I felt that my bones were dislocated, I got shocked, but I am not dead. My calculations say that I should die: the output voltage is 5 kV to…
pankaj prasad
  • 1,039
  • 1
  • 14
  • 17
61
votes
10 answers

Why is main's neutral tied to earth?

My dad is an Electrician and I myself am an Electronics Design Engineer, and to this day he still hasn't been able to give me a good reason for this. Consider the two following pictures/situations - both the same case, but with neutral not tied to…
DSWG
  • 1,620
  • 1
  • 12
  • 19
60
votes
9 answers

RTOS for Embedded Systems

I have seen many articles that tell me I should be using RTOS for time management and resource management. My time has not permitted my own research, so I come to chiphacker for advice. I use low resource microcontrollers(MSP430, PIC) and was…
Kortuk
  • 13,412
  • 8
  • 62
  • 85
60
votes
2 answers

In a USB cable, is it OK to swap the D+ and D- wires?

I heard that D+ and D- are differential signals, does it matter if I swap them when connecting a USB device to the computer?
Yan King Yin
  • 711
  • 1
  • 5
  • 6