The Element Cu known for its electrical and thermal conductivity, both of which are exploited in EE. THis material is typically what is used in PCB's for the traces and also modern CMOS processes have Cu layers in them due to it's superior conductivity. You also see copper in heat sinks to carry ...

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12
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2answers
1k views

Why is there copper on the side of this package?

I'm searching around digi-key when I noticed one of the MEMS oscillators has these copper pieces on the edge of the package: I'm not talking about the pads, I'm just talking about those little ...
-1
votes
2answers
66 views

I just bought a one-earbud headset with a microphone, but the jack is too small! I cut it open, what do the wires do? [closed]

So, yeah, this is my first question, yay, but I still have a problem, boo. I was on a rummage sale spree, so-to-speak, looking for a new pair of earbuds as yet another cheapie pair has broken. I ...
1
vote
2answers
66 views

Soldering thin polyurethane covered wire

Is it possible to "solder through it" or does it have to be fully stripped? The material is 0.15mm copper wire.
3
votes
0answers
106 views

I need to create a planar inductor with a specific value of 28 nH on a 4-layer PCB. How do I determine the proper trace geometry?

I am using a Linear Technologies LT-1534 part an need to create a planar PCB surface inductor with the specific value of 28nH; i.e., the inductor will be a copper trace on the PC boards Top Surface to ...
0
votes
0answers
77 views

Copper and Aluminium connection in Busbars

As you know, Pure Copper and Aluminium and its alloys are widely used in fabrication of electrical Busbars. According to watteredge, AA6061, AA5052, AA1100, AA1350 and AA6101 are the most common ...
2
votes
2answers
170 views

High voltage cable cross section

What kind of power and voltage can the cable in the photo possibly drive and why is it composed of a lot of small cables? What if the diameter of the single copper cables were a little bigger? How ...
1
vote
1answer
42 views

Loss of speed on error-free aDSL line [closed]

Is there such a thing as an old telephone line? Does a POTS cable deteriorate over time? I am talking about lines in area where no one lived 75 years ago. Sometimes a customer using an asymmetric DSL ...
2
votes
1answer
189 views

How does this prototyping style work?

I'm a little puzzled about a prototyping style I've seen used recently. Here is an example picture of a circuit made in this way: Can someone explain the process of making a board like this? Why are ...
-2
votes
2answers
131 views

How does a digital sound card's electric circuit make different pitches, etc. measured in just electrons? [closed]

I was wondering how hardware engineers, electrical engineers, or any and all inbetween design a circuit diagram for something that measures pitches, tones, etc. all in the form of bits/bytes and ...
0
votes
1answer
59 views

Coupling mechanisms

What are some mechanisms that one material can be coupled electromagnetically to another, other than basic tranformer action? The model I'm considering is a high current electrode, about 1.5m wide, ...
0
votes
2answers
155 views

Current carrying conductor axially through a copper ring

What effect would a copper ring around a current carrying conductor have on the current in the conductor? How can I go about mathematically modelling the current in the conductor? Details : The ...
6
votes
3answers
1k views

Is it better to have a poor top layer copper pour or no copper at all?

For a few small 2 layers boards I'm doing, I'm using the top layer for parts and signals and a ground pour on the bottom layer with no or very short traces, based on comments and answers to my ...
0
votes
4answers
773 views

Heating wire filament with low voltage / amps

Is it possible to heat either nichrome or copper wire (both 40 awg) with the following low-power delivery of 3.5 Volts, 7.4mW and 2.11mA? This is very low power delivery and we're wondering if 3 ...
5
votes
2answers
251 views

PCB Design Considerations - Copper Pouring

So after a very long effort, I think I've finally come towards the end of my PCB board design. It's a two layer board with no ground or VCC plains (Re-routing is not an option) as I can't go though ...
16
votes
2answers
887 views

Why are copper tracks orange-gold?

I have in front of me a raw PCB. The surface mostly has three colors: dark green, orange-gold and white. As I understand, the green is resist, the orange-gold is copper, and the white just the silk ...
19
votes
4answers
980 views

Why does water short out PCBs? (i.e. Why doesn't electricity follow the path of least resistance?)

If copper is more conductive than water (at any reasonable PH), submerging copper electronic circuits in should have no effect, as the electricity should continue to follow the path of least ...
2
votes
1answer
222 views

PCB Design - Copper Pour

I need some guidance on how to begin troubleshooting a specific problem with a bareboard. Board Info- Size-22"x26" Laminate-ITEQ Layers-30 In addition to standard bareboard ET (10v with 10Mohms ...
0
votes
2answers
266 views

Encoding delay of Ethernet and the relation to cable frequency rating

I asked a question here called "Speed of electricity (signal propagation?) through copper for communications delay". I wanted to know how long does it take a signal to travel down a length of Cat5e ...
1
vote
2answers
721 views

pcb damaged, broken copper any ideas?

I was trying to solder a new capacitor on my pcb and I had problems. At the end I think I burned the copper under the pcb mask and I am wondering if i totally destroyed my pcb. Here is a picture: ...
2
votes
1answer
581 views

How can I determine the resistance needed to heat a wire to a specific temperature? [duplicate]

Possible Duplicate: How do I calculate the temperature rise in a copper conductor? I want to have a AA battery heat up a copper wire .12mm diameter, but want it to heat up to 302°F, not ...
3
votes
4answers
2k views

reference source for copper conductivity vs. temperature?

I am looking for a curve for copper conductivity vs. temperature over the -55°C to +180°C range (covers std. ranges of semiconductors plus NEMA class H insulation in the case of magnetics / ...
0
votes
1answer
645 views

about power supply on what length of copper wire we should use

Could you help me on the equivalent current of three phase alternating current having 400v( volt ), 530 kw power and the available cross-sectional area of a copper wire, its length 350 m for carring ...
3
votes
2answers
306 views

Coils! Does the material used matter?

I've been making some coils with wires and I find out that sometimes they work and sometimes they don't work at all, the inside of those that don't work are some what more "silver-ish", more ...
17
votes
3answers
3k views

How do I determine the area of copper needed on a PCB to provide adequate heatsinking for a power SMD MOSFET?

I am planning to use the IRFR5305PBF Power MOSFET (http://www.irf.com/product-info/datasheets/data/irfr5305pbf.pdf) to switch on a load. I have determined that I need an external heatsink with Rthsa ...
4
votes
3answers
2k views

multi-layer board copper pour

I have a 6-layer board where the internal 4 planes are +15,GND,VCC,-15. I was wondering if there was any advantage to doing a copper pour on the top and bottom layers? I would probably leave them ...
6
votes
3answers
509 views

What would be the difference in a coil of wire and just a cylinder of solid copper?

Ok so I am learning about induction and I always see coils of wire with no insulator. So I was wondering, What is the significance of it being a coil of wire rather than just a solid cylinder since ...
8
votes
3answers
15k views

How do I calculate the temperature rise in a copper conductor?

If I pass a current through a copper conductor, how can I calculate how hot the conductor will get? For example, if I have a 7.2kW load powered by 240VAC, the current will be 30A. If I transmit this ...