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Why routing orthogonal signals with reference to the same plane?

Look at the return path of the coupled signal between the two traces. If they share the same reference plane, the return path is ok. If the two traces refere to different reference planes, everything ...
mlx11's user avatar
  • 160
0 votes

Ethernet controller EMC failure

The W5500 uses PLL to generate 125 MHz using 25 MHz crystal. Digital part and PHY are fed with this frequency. The chip is relatively hungry for the current as it contains PHY inside. And it is the ...
Anonymous's user avatar
  • 7,108
3 votes

Return current on PCB

I'm trying to understand why there is no return path inside the package? There is a return path, it is through the wire bond and the pin to the ground pin on the outside of the package. Sometimes the ...
Voltage Spike's user avatar
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3 votes

Return current on PCB

But there must be a return path. In a working circuit. Without a path the circuit would be open. If something like a pulse of current goes via a package pin into the chip through some bond wire, there ...
Justme's user avatar
  • 149k
6 votes

Return current on PCB

The image of the IC you showed has the ground pin (and ground bond wire) right next to the signal pin. That's the return path. On a typical two-layer PCB, you might have a distance of about 1.5mm ...
Jonathan S.'s user avatar
  • 18.9k
1 vote
Accepted

Investigating the effect of PCB layout parasitic in an op-amp amplifier by simulation

For simulation accuracy you need an accurate opamp model. Some models are quite simplified and only include the basics like open loop gain/phase and output impedance. Sometimes, the output is a ...
bobflux's user avatar
  • 77.6k
0 votes

Ethernet layout review: avoid vias or avoid copper under transformer?

As stated in comments by hacktastical: I’ll add that your Bob Smith termination is wrong. Should have a separate 75 ohm to each center tap, terminated to a 2kV cap. More here: Is my Bob Smith ...
1 vote

I am not able to see trace attached to component while dragging component in Altium

I have figured out how to enable track while dragging component must press N while dragging component and this should work
Monesh Rathod's user avatar
2 votes

Which shunt resistor placement is best?

You're right about the small track on the top "wrong" layout being an issue. But beyond current handling capabilities of the track, the current that is forced through there will cause some ...
Michael's user avatar
  • 516
4 votes

Which shunt resistor placement is best?

Probably to distribute the current over all three shunt resistors more equally. Keep in mind that those little traces connecting the pads of the shunt resistors also have resistance. In practice, the ...
feynman's user avatar
  • 3,365
11 votes

Is it good practice to place decoupling capacitors near connector pins?

There is no standard practice. It depends on the connector and what it is used for. You put a cap if you need it for some reason, or leave it out if there is no reason to put it. In some cases it's a ...
Justme's user avatar
  • 149k
10 votes

Is it good practice to place decoupling capacitors near connector pins?

People may put them near connectors if there is a possibility of ESD from external wiring damaging the chips on your circuit board. After all, you ideally want the transient to be dealt with at the ...
Andy aka's user avatar
  • 458k
6 votes

Is it good practice to place decoupling capacitors near connector pins?

Electrolytics near power inlet connectors can help reduce the overshoot from the interaction of long wire run inductance and low-ESR ceramic converter input caps (see: https://www.analog.com/media/en/...
vir's user avatar
  • 18.5k
5 votes
Accepted

Is this a "good" PCB layout for the BQ25798 IC?

Problem 1: Counterfeit LM2596 module. All these should be assumed fake. See these links: 0 1 2 3. It will kinda work, but it will draw high idle current, have high ripple, bad regulation, terrible ...
bobflux's user avatar
  • 77.6k
2 votes

Is this a "good" PCB layout for the BQ25798 IC?

Getting a good performing layout with a converter like this is a challenge with only two layers. A few things jump out at me. It looks like the switching nodes that connect to the inductor have many ...
Matt Hadler's user avatar
0 votes
Accepted

LED PWM traces splitting reference power plane adjacent to bottom 5V DC supply ground zone on 4-layer PCB

Your issues with the LED lines bring up two issues. One is the interruption of the return path for any signals crossing the gap. The return currents have to find their way around the gap, creating a ...
Cristobol Polychronopolis's user avatar

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