New answers tagged impedance
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Why is impedance represented as a complex number rather than a vector?
Impedance, by definition, is a dynamic property. It only relates to oscillatory behavior, i.e. electrical AC current or mechanical vibrations. The solution requires a complex number, mathematically.
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How do I simultaneously distribute a GPIO 3.3V logic signal to a batch of identical devices with 1.8V input
You probably can't transmit a 40ns pulse along a pair of wires without reflections obliterating the nice square edges, unless you properly terminate the transmission line at both ends.
Also, if you ...
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How do I simultaneously distribute a GPIO 3.3V logic signal to a batch of identical devices with 1.8V input
You need to rethink your circuit. The pico should be supplying the logic signal, but not the power. Use a transistor, or perhaps a buffer chip. And draw power from a separate source.
If you need 1.65V,...
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How do I simultaneously distribute a GPIO 3.3V logic signal to a batch of identical devices with 1.8V input
This won't work. The first part of the question is how to switch a load which exceeds draw from power source.
Obviously, there's no way to power a load that requires more than your supply can provide.
...
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How do I simultaneously distribute a GPIO 3.3V logic signal to a batch of identical devices with 1.8V input
How do I switch them all off then on rapidly without exceeding the max current draw of my power source?
You can't if you want them all on together.
There may be solutions to your real problem if you ...
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Derivation of Characteristic Impedance?
The chacteristic impedance for a transmission line follows directly from the Telegrapher's Equations and there assumption that the characteristic impedance doesn't vary along the line.
$$V_x=-LI_t-RI$$...
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Design of 13.56MHz RF generator circuit for driving capacitively coupled plasma
For plasma ignition the two type of systems had been traditionally used. First was the vacuum tube circuits exploiting the parallel resonant tank. Thus tube having anode voltage 1000-1500 V but max 50 ...
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How do you chain 2-port S-parameters onto a 1-port S-parameter?
From Wikipedia (or pretty well any rf/microwave text covering S-parameters):
https://en.wikipedia.org/wiki/Scattering_parameters
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RLC equivalent model and Impedance Smith Chart
I keep looking but have not found graphs showing the impedances of circuits at various vales of l&c. If the reactances of the L or C are higher supposedly the impedance seen at resonance will be h
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Output-Z (electret) higher than Input-Z (preamp)
Your High-Z microphone may struggle to provide the current needed for the Low-Z preamp, which in turn results in a smaller signal (as you mentioned). Ideally, for good amplification you want a Low-Z ...
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TDM signal conditioning
Your cable is probably 50 or 60 ohms single ended impedance.
This porch you see on the rising and falling edges of the signal indicates that whatever is driving the cable has an output impedance close ...
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TDM signal conditioning
TDM has 3 signals: Frame sync, clock, data.
Digression:
These need to be aligned in time properly. The source emits sync and data on the falling edge of clock, and the receiver samples sync and data ...
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Line-out vs headphone-out impedance
The point is you don't need as low impedance on line out when it is driving a 10kohm input, while the headphone output needs low impedance as it must drive 16 ohm headphones.
Also the difference is in ...
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Line-out vs headphone-out impedance
Both are low impedance outputs, with some differences:
For a line out, output current is negligible so it is not a selection criteria for the opamp driving it. In addition, a low value series resistor ...
- 72.1k
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Tri-state buffer, why is it called high-impedance?
The problem
Isn't it so that when we have high impedance it is neither connected to low or high?
Yes, but how do we know that it is in this state and not in LOW? An interesting problem is how to ...
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Tri-state buffer, why is it called high-impedance?
When one of the output drivers is on, we can say there is pretty much short circuit from output to either supply or ground, so in real life, a very low impedance anyway.
When both of the output ...
- 138k
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Tri-state buffer, why is it called high-impedance?
Resistance is the real part of impedance.
When the output is disabled, it draws very little current if something else tries to change the voltage. It doesn't significantly load any circuits connected ...
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