Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [bypass]

For questions about bypass capacitors, which are used to bypass an AC signal or noise to ground. They are usually found connected between the power supply and ground pins of integrated circuits to improve the power supply connection for the integrated circuit.

For questions about bypass capacitors, which are used to bypass an AC signal or noise to ground. They are usually found connected between the power supply and ground pins of integrated circuits to improve the power supply connection for the integrated circuit.

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Where did the value of 0.1uF for bypass capacitors come from?

Nearly everyone recommends 0.1uF for bypass capacitors. Why this value? I assume there is no harm to using larger values so is it merely a "sensible minimum"? And if so why do people go for the minimum rather than using higher values - it seems to…
Timmmm
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Placing bypass capacitors after VCC reaches the IC

I have a question about bypass capacitors and their possible placements. I am designing what I hope to be a double sided PCB, which has the VCC and the vast majority of the data lines on one side, with the majority of the other side as a GND plane…
Alister Smith
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Why should the smallest bypass capacitor be placed nearest to the IC?

I have found and read many papers about bypass capacitors, but there is still one thing I am really struggling with. Let's say I have an IC and I place 3 bypass capacitors (eg. 10µ, 1µ and 100n). I am familiar with the idea that the smallest should…
Tomáš Havel
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Capacitor with specific self-resonant frequency?

I have a datasheet that calls for "a 15 pF capacitor with Self-Resonant Frequency in the 1800/1900 MHz range". It then recommends a capacitor (Murata GRM1555C1H150J) that (so far as I can tell) from the datasheet doesn't specify it's SRF. I'd like…
Britton Kerin
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What does "Bypass capacitors on both sides of the package" mean?

I am beginning my first electronics project, which is a PCB that holds a 3.3V flash, and interfaces it with a 5V system for reading and writing. The model of flash I am attempting to integrate is the S29GL032N, its datasheet is here:…
Alister Smith
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LDO with a bypass option?

I want a board I'm designing to accept either 5V or 3.3V power as input. If 5V power is supplied I want to generate 3.3V regulated power on board. The rest of the board all runs off of the 3.3V power. If I call my input power VDDIO, and VDDIO = 5V,…
vicatcu
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Smaller footprint for SMD capacitors

I'm (again) placing bypass capacitors around an FPGA, and can't seem to get to a sane solution, given that I have all the pins assigned, and the supply pins are right in the middle of the I/O pins. As an example, placement around pin 1: The next…
Simon Richter
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How does a NOT gate bypass the output?

I have found the basic tutorials on gates and the way they work. However, I'm not understanding conceptually how a NOT gate, when activated, bypasses the output. Circuit as follows: simulate this circuit – Schematic created using CircuitLab When…
Robbers85
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Are there flaws in the reasoning behind the Zedboard bypass scheme?

There is an eval board for the Xilinx Zynq-7000 FPGA called the Zedboard. When you look at the board you will notice a very interesting pattern of bypass capacitors. The designer has a technical note that explains why he/she thinks this is a good…
Rolf Ostergaard
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Bypassing a voltage regulator if input voltage is too low

For my project I want to allow the user to either use a 12 or 24VDC power adapter if needed but I dont want to make 2 seperate DC inputs. Neither do I want to use a buck-boost because I dont want to regulate the 12V voltage but most bucks only work…
Daniel Do
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Why do we need 4 resistors for a common emitter amplifier?

I'm studying the 4 resistors bias configuration, I'm trying to understand why we need everyone of these resistors. If I understood correctly, Re is used to make the Q-point stable, while R1 and R2 are used to determine Vbe, but I can't understand…
Juà
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Faster settling time for near DC pole low pass filter

I need to clean up the noise from a voltage reference and I wanted to use a simple RC low pass filter. In order to lower the pole position I have to use a big resistor and/or a big capacitor. As the voltage reference should not have much intrinsic…
KBowser
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Suppression capacitors? What type should I use?

I'm building a digital power base for a Scalextric slot car track using the schema provided here (you might have to click the "Powerbase Circuit" tab). Now, my question is, what type of capacitors should be used for C7 and C8 (the right-most ones…
Anttu
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Bypass/decoupling capacitor type choice

Having different types of capacitors (electrolytic, film, silicon, tantalum, etc.), which types would be the optimal choice for polar/non-polar pair in this common configuration: I understand the reason for having two or more caps of different…
Nazar
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Why am I not getting the expected simulation output in LTspice after adding bypass diodes to my PV module?

I am trying to simulate solar cells of a solar module with 72 cells and see the effects of partial shading and the activation of bypass diode. For now I am just simulating 2 cells of the PV module as shown below: I am confident that the model works…
Mayur
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