Questions tagged [impedance-matching]
Impedance matching is a process of making one impedance equal to another another.
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How do I lay out PCB traces for a given "differential impedance"
This is an attempt to craft a good general question and answer for a topic that's been asked before, but only in specific situations.
Could you describe what I need to know, prior to laying out a PCB ...
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Why Characteristic Impedance must be 50 ohms?
Where does this number come from?
For single ended it must be 50 ohm and for differential pairs 100 ohm. Why?
For PCB with controlled-impedance these are that common numbers. Outside of the PCB you ...
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What's the importance of source impedance termination?
Given a circuit like this:
simulate this circuit – Schematic created using CircuitLab
What's the importance of R1? One can guess that it's to make the output impedance of BUF1 equal to the ...
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Why are common mode chokes with 90 ohm @ 100 MHz recommended for USB 2.0 Hi-Speed data lines?
When one looks at common mode chokes for USB 2.0 applications choke manufacturers always recommend CMC with a common mode impedance of 90 ohms @ 100 MHz.
Example
How does this relate to
USB 2.0 ...
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What can reduce overshoot and ringing on a simple square wave pulse generator?
I've built a simple RC and Schmitt-trigger-based square wave pulse generator. On the breadboard, it has some obvious unwanted qualities due to jumper length, the breadboard itself, etc.
Schematic and ...
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Effects of impedance matching between 50 and 75 Ohm coaxial cables for 10 Mbit/s, Manchester-coded signals (20 MHz)
TL,DR:
This is quite a bunch of text because I have included plenty of background info. However, there will finally be a good, and precise question: Should I use an impedance matching network when ...
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Output impedance of STM32H743 MCU?
How do I find the output impedance of the STM32H743 (and potentially other similar devices)? I've looked through the datasheet (DS12110 Rev 5) and the reference manual (RM0433 Rev 5) however haven't ...
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Simplest way to check if an audio level is line or micro?
I can check level audio on a VU Meter or dBFS meter. What's the simplest way to check if an input audio level is line or micro? Can I use a multimeter?
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Power supply for toothbrush motor
I would like to connect an electric toothbrush motor (Braun Oral-B Type 4729) directly to external power supply. So far I have been trying at least 3 different DC power supply unit with appropriate ...
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(When) Can I use Cat5e wiring to carry a POTS signal to a DSL modem?
According to this answer by @asndre,
It is very bad idea to use Cat5e-based wiring/cabling to establish a
xDSL connection.
However, my telephone/internet provider technician recommended -- and ...
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How to match RF output of (30+j10) Ohms to 50 Ohm antenna with matching network?
I'm designing a matching network for a 2.4 GHz inverted F antenna on a PCB that I am also designing. I am using an ESP32-D0WDQ6 MCU, and reading from the datasheet, the output impedance for the RF pin ...
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Impedance Matching Resistors on MII Ethernet Lines
Microchip is taking forever to activate my account so I will ask this here...
I am using the KSZ8081 PHY for MII Ethernet.
https://www.mouser.com/ProductDetail/Microchip-Technology-Micrel/...
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Why does "impedance matching" in the context of reflections demand that resistive impedance and reactive impedance are treated separately?
I have assumed that for reflections, Ohm had to be matched between source and load, but resistive and reactive impedance did not have to be matched separately. I was told this is wrong, and that ...
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Impedance matching in RF and complex conjugate (Maximum power transfer theorem)
The "maximum power transfer theorem" states that "maximum power transfer occurs when the load impedance is equal to the complex conjugate of the source impedance", that "for ...
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Impedance matching with L-matching network: cooking recipe
I would like to try to elaborate in detail how I think one should perform in detail practically
impedance match between source and load via maximal power transfer using
a L-matching network and whould ...
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