Skip to main content
Electrical Engineering

Questions tagged [decoupling-capacitor]

Ask Question

A capacitor, usually ceramic, used to provide instantaneous energy to a local circuit.

558 questions
Newest Active Bountied Unanswered
Filter by
Sorted by
Tagged with
3 votes
2 answers
499 views

I’m working on a non-inverting op-amp circuit with: AC input: 1 Vpk at 1 kHz DC offset: 2 V in series with the AC signal Gain: 3 V/V ±12 V power rails There is significant simulated noise on the ...
Omuse's user avatar
  • 411
0 votes
1 answer
105 views

To be specific about the part, it is LFE5U-45F-8BG381C in 381-FBGA. I have at least one ground plane and two power planes (one for VCCIO and one partitioned for VCC and VCCAUX). However I want to ...
Hammdist's user avatar
  • 631
-1 votes
1 answer
102 views

My PCB stackup is SIG1/GND/VCC1/VCC2/GND/SIG2. At the title says, how should I select capacitors for stitching ground and power planes near a differential pair for ...
Hammdist's user avatar
  • 631
1 vote
3 answers
192 views

In this application notes I have some confusion. Here it is written that "Therefore, choosing a low-inductance but high-value capacitor (low impedance) is very important." My question is if ...
khatus's user avatar
  • 77
2 votes
2 answers
248 views

There is a plan to do PDN decoupling simulation for the KSZ9897RTXI power rails. It has various power supply like 1.8V, 2.5V& 1.2V. While doing the simulation, what is the maximum frequency range ...
Potionless's user avatar
  • 1,819
6 votes
1 answer
585 views

I was researching the use of controlled ESR capacitors for decoupling and I wondered what part numbers there are for these capacitors. For those who don't know controlled ESR capacitors are MLCC ...
BORA Kocabaş's user avatar
  • 71
0 votes
2 answers
117 views

I am prototyping a signal processing project on perfboard. Since I am very new to electrical stuff (high schooler), I'm not able to solder smd comps very well. I need to decouple a couple of ...
user16283158's user avatar
  • 49
0 votes
2 answers
133 views

What is your opinion on using a 100nF capacitor in the digital input circuit with the PC817C optocoupler? I am using this capacitor to eliminate false triggering from the pushbutton. When the ...
Ahtisham A's user avatar
  • 393
1 vote
3 answers
249 views

I was discussing about decoupling capacitors for ADC in this forum. One user commented as shown below. The thing is, the smaller 0603 SMD capacitors have a higher internal resistance compared to the ...
Confused's user avatar
  • 4,055
0 votes
0 answers
44 views

Assuming you routing a PCB were you using an IC with a BGA package. Your mission is to: Preserve the inteplane capacitance Fit decouplings capacitors (0201 or 0402) onto the BGA vias Not using blind ...
euraad's user avatar
  • 1,466
4 votes
4 answers
661 views

I am using ceramic capacitors of values 0.1 µF and 4.7 µF in parallel as the local storage and decoupling on my STM32 microcontroller IC. I have one 0.1 µF for each Vdd pin as recommended in the ...
Gokul Karthik's user avatar
  • 577
0 votes
0 answers
40 views

Test Principle Overview: The test setup involves multiple catheter rings connected through relays. During each test cycle: We apply +300V DC to all but one of the rings (via relays). The remaining ...
Dew_1225's user avatar
  • 13
1 vote
1 answer
54 views

Where do I find the decoupling capacitors to use for the MK66FN2M0VLQ18? Whenever I look for more general help, I am told to just check the datasheet. I can not find the information on the datasheet ...
Rocket Man's user avatar
  • 59
4 votes
4 answers
838 views

I am trying to understand how to wire up MCU schematics on my own. I know what decoupling capacitors are. What I don't understand is why they are using this weird configuration. Why are there only 3 ...
Rocket Man's user avatar
  • 59
0 votes
1 answer
101 views

Following this reference I have designed a low noise electret microphone amplifier. I will feed it from a standard 9V battery and was wondering if adding capacitors C2 and C3 would have a significant ...
Phönix 64's user avatar
  • 139
12 votes
5 answers
1k views

I have a 4 layer PCB, and I'm trying to shove as many addressable LEDs as physically possible onto the front layer. The inner layers contain a power plane and a ground plane, and I'm using in pad vias ...
Rick de Water's user avatar
  • 273
3 votes
3 answers
214 views

I am making a amplifier that consists of an input stage (differential pair and current mirror etc), a voltage gain stage (Sziklai pair) and on the end I want a classic AB push pull output stage to ...
CaptainDavid's user avatar
  • 31
2 votes
1 answer
78 views

I am designing my first PCB and it uses an STM32WBA63 MCU. In the power scheme diagram (p97 of the datasheet), it is written "n x 100nF + 10 µF" for the corresponding n VDD pins (in my case: ...
TheChade's user avatar
  • 197
2 votes
1 answer
133 views

I have a number of binary input channels at 13.8v level running into a Raspberry Pi via a CNY74-4H Transistor Output Optocoupler. I have pull down resistors on the inputs to the Optocoupler, and I'm ...
Matt's user avatar
  • 31
12 votes
10 answers
2k views

In this example we have an ATMEGA328 microcontroller with a number of VCC and GND inputs. The PCB is 4 layers with internal ground and power planes. In my understanding the best practice for placing ...
Hneel's user avatar
  • 309
3 votes
1 answer
134 views

I am having some trouble with routing the connections to a BMP390 barometer. In order to make more space for the SPI CLK line, I was wondering if it would be OK to route through the decoupling ...
Ryderr's user avatar
  • 315
3 votes
1 answer
76 views

I'll often use tools for designing switching regulators that will give me a recommended amount of bulk decoupling to handle some amount of step load to get a desired transient response and ripple. ...
Spencer Ford's user avatar
  • 31
4 votes
3 answers
588 views

I am working on my hobby project and I am little bit confused about decoupling capacitors size. In their Getting Started document there is a table on page 10 with recommended sizes. For power, they ...
Fero Garzonka's user avatar
  • 51
1 vote
2 answers
83 views

I am working on hobby project (game console with gameboy emulator) which includes STM32MP135 microprocessor. I am not very experienced but I have done a few other projects with their MCU series so I ...
Fero Garzonka's user avatar
  • 51
1 vote
1 answer
76 views

In this online tool, There's a field called power supply (in mohms and nH) and plane capacitance (mohms and uF). I have 2 questions. How does the power supply and plane capacitance impact the graph ...
Potionless's user avatar
  • 1,819
1 vote
0 answers
80 views

I was wondering the following: When using differential line driver ICs such as the THAT1646 and DRV134 it is recommended to use feedback into the 'sense' pins to reduce common-mode offset + using the ...
Lex Geurts's user avatar
  • 23
0 votes
3 answers
271 views

My circuit works in simulation but when tested with real circuit I am still getting negative DC offset. My AC voltage is -8V to +8V with frequency 16Hz. When simulated all is fine but with voltages in ...
Todoroki Gokiburi's user avatar
  • 13
0 votes
1 answer
77 views

The CONTROL IN signal on a Pioneer A50 amplifier is used to daisy-chain multiple Pioneer devices together, allowing them to be controlled by a single remote control. In essence, the signal from the IR ...
LastStarDust's user avatar
  • 51
-1 votes
1 answer
66 views

Why this PMIC has Via between capacitor and PMIC pins? Does it break the flow? Is this good layout practices If yes then how?
Monesh Rathod's user avatar
  • 169
1 vote
1 answer
136 views

I am currently designing a PCB which will use the Texas Instruments LP876242-Q1. The board is a similar board to their TIDA-020047 reference design, so I am studying their design decisions. One ...
Willjiggs's user avatar
  • 65
0 votes
2 answers
111 views

I'm totally new in PCB design, especially design with SMD components. Please help me understand what I'm thinking wrong. I'm thinking about placing 3 TMC2226 Silent stepper motor drivers on the same ...
dboodbc's user avatar
  • 1
2 votes
2 answers
124 views

I am having trouble with "duplicated" signals when my microprocessor receives digital input. I think that the lack of proper decoupling could cause the issue, but I don't have the knowledge ...
Tales Hein's user avatar
  • 21
1 vote
1 answer
359 views

Problem: I have an issue obtaining the correct circuit equations for these coupled LC circuits. Attempted solution: We obtain the equations of motion for the capacitors by using Kirchoff's law for a ...
FriendlyLagrangian's user avatar
  • 149
1 vote
0 answers
75 views

For BGA packages, I never see people tying power/GND pins together on BGA package (e.g. tying +1.1V_FPGA pins together as shown). Usually I see one ball to one via like how the GND is layout as shown. ...
Peter's user avatar
  • 99
6 votes
9 answers
3k views

In the case of bypassing/decoupling capacitors under DC circuits, I know that they act as open circuits when connected between Vcc and ground, which is why the two can be shorted, but why/how exactly ...
eutectic_codswallop's user avatar
  • 173
4 votes
4 answers
642 views

From what I have read so far decoupling caps help in reducing the supply droop due to trace inductors in case the load draws large current transients. The capacitor works to supply the current ...
needbrainscratched's user avatar
  • 959
1 vote
1 answer
111 views

I am working on a mini drone project. For the power supply, I am using a 1S LiPo (3.7 V) battery with a Schottky diode for protection. I plan to use a decoupling capacitor to handle rapid voltage ...
Ovln's user avatar
  • 45
1 vote
1 answer
158 views

I have a question about the return current for signal traces that are routed in the inner layer of a six layer PCB. I am designing, like I said, a six layer board. The stackup is like this: Layer 1: ...
Djumbonia's user avatar
  • 131
0 votes
1 answer
149 views

I read in the AdaFruit guide that a 500-1000uF capacitor is recommended on the power rail. However, electrolytic capacitors in this capacitance are quite large. Depending on the length of the strip, ...
DennisFrett's user avatar
  • 151
4 votes
5 answers
781 views

Source: https://tangentsoft.com/elec/vgrounds.html I am trying to design a circuit using a single battery as shown in the image above, I am worried that all the decoupling capacitors that will go from ...
Pranav Agumbe's user avatar
  • 71
0 votes
0 answers
62 views

Short question first If I want to use an emitter-follower to strengthen a signal source and I need a bias network for the transistor, how do I isolate this from the source if the source is digital? ...
palako's user avatar
  • 164
0 votes
2 answers
510 views

I've a new ESP32-H2 that works fine as a Matter device if it is powered from USB port. When I try to power it from 3V3-Battery pin using a very reliable power supply (Keithley Model 2231A-Triple-...
M4Biz's user avatar
  • 359
0 votes
3 answers
124 views

Do I need decoupling caps on each V+ pin of my I/O expanders when they're all sharing the same 5 V supply?
Rue D's user avatar
  • 1
1 vote
2 answers
235 views

when in the refence design of an amplifier (for example OPA856) we see the + sign in a capacitor schematic, does this necessarily means we should use electrolytic capacitors? If there is no positive ...
Andromeda's user avatar
  • 1,438
0 votes
0 answers
70 views

I have a new 4 layer board (Pwr/Sig, GND, GND, Pwr/Sig) that is behaving in a way I don't understand and some how "back powering" a 5v plane it shouldn't be able to. The board is in 2 ...
Neil's user avatar
  • 153
3 votes
2 answers
1k views

Normally for opamps supply voltages, it is suggested that there should be (100 nF + 2-10 uF) on the positive and negative supply pins. The second capacitor which is in range of uF should tantalum? Or ...
Andromeda's user avatar
  • 1,438
1 vote
1 answer
141 views

What is the purpose of these 10nF capacitors on all the ECU input pins? Image source: https://www.finjector.com/documents/647ef11579093/TKU-0261230340-.pdf, section 2.4. Error diagnosis
featherbits's user avatar
  • 221
1 vote
1 answer
109 views

Background The TI TLC6983 LED driver datasheet provides decoupling capacitor recommendations for the IC and LED supply pins, in ...
kando's user avatar
  • 457
0 votes
3 answers
143 views

I am familiar with adding decoupling capacitors to protect input power pins of chips on PCBAs, as well as output power pins of voltage converters. Still, there is something I am not sure of. Below are ...
uz3il's user avatar
  • 495
8 votes
3 answers
3k views

I’ve seen some notes online about placing decoupling capacitors near I/O connector pins, as well as some saying power lines of connector pins. Despite this, I feel that I haven’t often seen capacitors ...
cs_eng_516's user avatar
  • 161

1
2 3 4 5
…
12