Questions tagged [high-speed]
High-speed design deals with designing circuits which are working at high frequencies where side-effects like path inductance gain significant influence.
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Why does a MOSFET fail on fast signals, even if they're much longer than the turn on + turn off times?
When running at a fast signal, why does the MOSFET below not turn off, even when gate voltage is well below threshold (even negative)? Although the signal is fast (7 MHz, 140 ns period) it is < 1/...
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How are pad impedance discontinuities precisely compensated for in high speed PCB layouts?
I stumbled across a recommendation in an 850MHz opamp datasheet that said the following:
All ground and power planes under the input and output pins must be cleared of copper to prevent the formation ...
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Display port eye diagram evaluation
I was testing my display port diagram, all 4 lines.
The first three look good, the 4th line looks like it has only one signal (not differential.)
My question:
Is the 4th line okey to be like this. (...
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Oscilloscope slow sampling with GPIB
I have a 12 GHz oscilloscope with a 40 GSa/s sampling rate from Keysight, and I have a National Instruments GPIB-USB-HS with it. Sampling for 30 seconds with no averaging of data, it only gives 20 ...
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Should reference plane change its potential value if a track goes to another layer?
Assume you have a four layer board.
Signal
GND
Dielectric
VDD
Signal
And you having a track in the 4:th layer. Suddenly you're using a via to go through the 4:th layer to 1:st layer.
Question
The ...
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Noise Fluctuation with MAX40660
I am currently implementing MAX40660 as a high speed TIA amplifier. In the process of testing the basic functionality of the circuit, I have implemented a pcb design similar to the evaluation kit. ...
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Removing GND and Power planes under the feedback pins and traces in opamp layout
I want to use a reference design form Texas instrument as a reference for my layout for OPA838, I noticed this reference design is a 4-layer board (signal-GND-Power-signal):
Reference: the image is a ...
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How can I analyze HighSpeed traces what on Proteus project file?
I designed a few PCB on Proteus what includes High-Speed signal traces(USB, Displayport, GigaEthernet etc.). I want to analyze that High-Speed Traces. I expect see some values like eye diagrams, ...
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What happens if there is an impedance mismatch on differential pairs? [closed]
What do we encounter if the impedance changes along the way? For example, what kind of problem can we encounter when one of the two complementary PCB's is 90 ohm and the other is 100 ohm? For example, ...
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Which of these 2 phenomena occur first - AN or MDIX
Most of these days, the Ethernet PHY/switch devices support Auto-MDIX and Autonegotiation.
So, when a link partner is getting connected to a PHY or a Switch, which of these two phenomenons happens ...
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How to achieve 50 Ohm Impedance with a SMB connector
I have a PCB design with a SMB connector but can't find any information about how I should treat the pad to ensure 50R impedance.
Should there be a keepout on the ground layer directly beneath this ...
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Why does this pulse generator have a voltage inverter?
I am designing a fast pulse generator, inspired by Leo Bodnar's pulse generator, using the ADCMP572 ultra fast comparator.
It looks like a pretty simple device, using a PIC microcontroller to drive ...
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Can I measure the internal termination resistance of a MIPI receiver?
This question is further to: How accurate are internal terminators on chips with high speed differential inputs?.
I would like to measure the actual termination resistance inside one of these chips (...
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Is a gap needed with LVDS with metal layer below it?
I have a 1.8 V, 350 MHz, 100 Ω LVDS signal on an FFC on the bottom plane. Below the FFC is an aluminum metal layer; the aluminum is pretty much unconnected from the FFC. The air gap/solder mask gap is ...
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FT2232H PCB routing (high speed)
This is the first time I am making a high speed PCB so I am a bit unconfident.
the ic I am talking about is this: FTDI232H
I have followed the schematic in the datasheet above and I have placed the ...
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