# Questions tagged [esr]

ESR is the "equivalent series resistance" of an electrical component (such as a capacitor or inductor) arising from non-idealities that are always present in the materials used in their construction.

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### ESR of aluminum electrolytic capacitors [closed]

Is there any way to calculate the ESR of electrolytic capacitors for high frequencies? In aluminum electrolytic capacitor datasheets, the dissipation factor is given with low frequency(100Hz-120Hz) ...
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### When taking into account ESR, the effective capacitance of parallel capacitors is not the sum of discrete capacitance?

I am trying to simulate the frequency response of a buck converter's control loop. The vendor's simulation tool is pretty limited and can only include one output capacitor. Therefore, I am trying to ...
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### How to calculate specific heat capacity of film and electrolytic capacitors?

I am trying to build a thermal equivalent model of a capacitor and its ESR in Simulink. I know the heat flow rate going into the capacitor, as well as the thermal resistance value, but I am missing ...
1 vote
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### Why does high frequency decoupling require a small capacitor?

Why can't a large ceramic capacitor with low ESR feed at high frequency? Maybe becase of resonance, since the higher freqeuency resonance can be achieved by lower C and ESL both not only equivalent ...
63 views

### Finding ESR of LCR circuit?

I have an LCR circuit, and I am trying to find the ESR of a capacitor. I bought a 820uH inductor , and an ultra-low 1000pF capacitor, and a 46.6ohm 1% tolerance resistor. Below is my circuit with ...
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1 vote
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### Low ESR capacitor: what does it mean/how to select one?

I'm trying to design a PCB including a TPS5450 step down converter. For the boost capacitor, the datasheet asks for a "low ESR ceramic capacitor": 7.3.5 Boost Capacitor (BOOT) Connect a 0....
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### What is the difference between ESR and DCR?

I am measuring the inductance of a large coil using an LCR meter. I am using the series equivalent measurement mode at 100 Hz. Why does the LCR meter show that the ESR is 656 Ohm and why does my ...
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1 vote
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### Calculating the real power consumed in a two-port network using its S-parameters

I would like to express the real power consumed in a two-port network using its S-parameters. Assume for simplicity $\underline{Z}=R\in\Re$ (1) My idea was using energy conservation:  P_{in} = P_{...
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1 vote
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### What is the Dissipation Factor of a capacitor useful for in its direct form?

Why do electrolytic capacitor makers provide the low frequency ESR in the form of a dissipation factor (DF) instead of an Ohms value as they do for higher frequency. The DF is rather unwieldy and I ...
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1 vote
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### Following is an excerpt from a power electronics textbook. Is the statement true?

As far as I know ESR primarily depends on the type of dielectric. eg: Al electrolytic (higher capacitance value) would have much higher ESR than ceramic (usually lower capacitance value). Say for ...
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### Modelling ESR of a parallel plate capacitor

I am trying to model a parallel plate capacitor (on die capacitor generated using metal plates.) I know the capacitance per unit area, and metal sheet resistance. No knowledge of the dielectric. I ...
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### Problem in capacitor selection

The SIM800L datasheet suggesting a low ESR capacitor for providing a 2 ampere burst current during data transmission. According to this site MLCC provides the lowest ESR at high-frequency application, ...
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### Equivalent series resistance vs. parallel leakage conductance

I am studying a book called RF Circuit Design by Reinhold Ludwig and Gene Bogdanov (2nd Edition). In the first chapter on capacitors, they introduce the loss tangent and equivalent series resistance, ...
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### Typically, do same-sized SMD ceramic capacitors with different capacitance have different ESR?

I know that depending on the dielectric, the technology, the company etc, but typically, if say two SMD ceramic capacitors are the exact same size (also of the same technology if you wish,) and their ...
194 views

### Powering microcontroller with a capacitor

I have a ESP32-SOLO-1 microcontroller mounted on a moving part of a machine which moves in a circle. The idea is to power it with a capacitor and then charge the capacitor in a fixed location when the ...
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### Estimation of Electrolytic Capacitor ESR at SMPS Frequencies

While working on compensation networks or ripple calculations, it helps to know the ESR for my output capacitors. In high voltage SMPS systems, this seems to be difficult for the following reasons: ...
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### Do touchstone (s2p) files for capacitors from include the ESR/ESL, or do I need to add an ideal R/L for simulation?

Manufacturers like muRata and AVX provide .s2p files for their RF capacitors. When modeling for simulation in my EDI software, do I need to include the ESR graphed in the datasheet for the frequency ...
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### Supercapacitor as PMIC Storage Element

I'm currently trying to design a system that incorporates an ADP5092 which can use a supercapacitor as the storage element but I am also considering other similar PMIC chips so this is more for ...
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### Capacitors: 200 mOhm ESR @ 100 Hz, attainable?

The MLCCs in 0805 case seem to have one or two orders of magnitude higher ESRs at that frequency. Are there any such low ESR caps out there, preferably 0805 MLCC but not compulsory? It is a 220 nF cap ...
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1 vote
123 views

### Capacitor ESR Calculation

I'm trying to perform esr calculations of this capacitor(1uF): https://alconelectronics.com/wp-content/uploads/2020/06/KP-6-JUNE-2019.pdf to do that I need to know dissipation factor and at the bottom ...
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### State Space Average Model of Non-Ideal Buck Converter

I've been learning power electronics and am trying to design a dual-switch forward converter. One of the things I've been trying to do is derive the small-signal equivalent circuit of the non-ideal ...
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### Is there a reliable way to read an in-circuit capacitor? [duplicate]

Is there a reliable way to read an in-circuit capacitor? I have a PCB-type ESR meter with a zero-force insertion socket that works for components, but do not have a meter that was designed to read ...
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### Buck Converter Capacitor and Inductor Characteristics

I'm trying to make a buck converter with this mickey-mouse MC34063A chip that will step-down +5V to +3V3 up to 500 milliamps. I've gone through the calculations by hand and validated them with an ...
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5k views

### Difference between "|Z|" and "Resistance" in capacitor datasheet?

I'm shopping for capacitors, and I expect good capacitor datasheets to have a graph of |Z| (the magnitude of the capacitor's impedance) as a function of frequency. I was confused when I looked at ...
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### Capacitor Impedance ESR vs Frequency Curve

Yageo's SMT capacitor datasheet lists the ESR vs. Frequency Curve show below: Note that impedance (Z) is listed in units (W). How can this be understood? Why is impedance seemingly not measured in ...
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### Strange Behaviour of Lipo Battery ESR during charging

I performed three charge tests on a single cell 190mAh Li-Po battery with Keithley Battery Simulator instrument. Charging started at 3V and stopped at 4.20V in all tests. After completing the three ...
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### Low ESR capcitors for switching pre-regulator (LM2596)

In LM2596 switching regulator datasheet suggested to use low ESR capacitors. since I'm going to use LM2596 as a pre-regulator for a linear regulator to reduce the voltage drop on linear regulator, is ...
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### Bulk Capacitor Ripple Current as a Function of Capacitance

When you have a bulk capacitor on a time varying load, what is the relationship between the capacitance of the bulk capacitor, the ESR of the bulk capacitor and the ripple current through the bulk ...
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### How to convert capacitor impedance to ESR?

I select an output capacitor for a DC / DC converter (LM2596), it is said that it needs a high ESR (50-60mOhm). In the characteristics of electrolytic capacitors there is no given value, but there is ...
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### stm32f7x2Rx vcap1 finding a suitable low ESR capacitor

According AN4661 In the STM32F7x2Rx devices, only the VCAP1 pin is available and must be connected to 4.7 µF low ESR between 0.1Ω and 0.2Ω ceramic capacitor. So how do I go about finding a ...
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### Normal ESR Values for Capacitors of Various Types

I am working on a light detection preamp board that went bad. The circuit uses a chopper stabilized opamp TLC2652. Does it have a reputation for being fragile? Anyway, as usual, I went around to ...
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### Crystal's datasheet give load capacitance is 20pF, do I need external load capacitors?

I use external crystal for HSE of STM32F0. I plan to use 8MHz Cylinder Crystals. Datasheet of this crystal below Datasheet give crystal load capacitance is 20pF My questions: 1/ Do I need to add 2 ...
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### What is an ESR zero in a power converter's output filter ? (#ExplainLikeI'm5)

I'm trying to understand this sentence (from this answer): So if your application has high ripple current and you don't need the ESR zero for stability then a low ESR cap will likely be the way ...
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### Why do some devices use electrolytic capacitors instead of ceramics for small value components?

I've recently run into a number of consumer-grade devices that use 50v, 0.22uF electrolytic capacitors, as well as other similarly rated parts, all below about 10uF. In use, the voltages on them are ...
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### Best method to determine current in ESR meter

I've recently found the need for a ESR meter(My daughter and her boyfriend brought me 8 broken LED/LCD TVs and 6 have power problems). I also decided to go all out and build a full blown ESR meter. ...
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### Trying to understand ESR

New here, self taught, been working with tube amps for a while. Currently working on my 64 Deluxe Reverb that I have restored to stock, with some of the original ceramic and film capacitors. Just ...
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### What causes the series resistance in capacitors?

Especially in high frequency circuits there often seems to be the problem of ESR of capacitors. ESR apparently is a characteristic of non-ideal capacitors, and is essentially a resistance appearing in ...
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### Calculating the ESR of Capacitor

I try to calculate the ESR of a capacitor. I checked this datasheet: http://www.farnell.com/datasheets/2245214.pdf?_ga=2.167304311.817060034.1534770853-676261198.1531404202 I can see from the ...
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### Crystal's ESR or Frequency Stability/Tolerance, which is more of a priority?

I'll be using a 12MHz crystal, CL=20pF on an NXP chip. Currently choosing between lower ESR (60ohms vs 100ohms) or lower stability (50ppm vs 10ppm). Which spec is more important? Should I choose a ...
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1 vote
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### How to convert Ripple Current spec to ESR?

It used to be that vendors like Digikey gave a cap's ESR value and not ripple current. Nowadays, it seems more report only ripple current and not ESR. What gives with that? So what are we supposed to ...
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### By-Pass Capacitors for my SIM7600 Module

I am designing a PCB for SIM7600 module. I am stuck at choosing right capacitors for it. The datasheet (Page 21 & 22) specifies the load transient of the module. You can found load transient below:...
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### 1117 voltage regularo ceramic caps

I have made a mistake and I do not have the space on my PCB to add two serial resistors. Is it OK to use only one for two caps? Simulation looks OK but it only the simulation
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### ESR of capacitor

ESR results in power loss and inefficient power supplies or regulators. How does ESR affect the stability of the system?
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### What's the impact of a crystal's frequency stability, ESR and load capacitance on micro-controllers?

I'm choosing a crystal for MK20DX256VLH7, but I can't seem to find enough information in MK20's datasheet for the oscillator. So, what I'm interested in knowing is: What is the impact of crystals' ...
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### LDO Output Capacitor Selection and ESR Consideration

For a simple application of a voltage regulator with 5V in and 3.3V out, I am looking at these three regulators. 1)AP2127K-3.3TRG1 2)MIC5504-3.3YM5-TR 3)TLV73333PDBVR They all have different ...
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### LM2596 and other DC-DC converters why oscillate if the output capacitor ESR value is too low?

I would like to use LM2596 converter. Datasheet says: 'If the selected capacitor's ESR is extremely low, there is a possibility of an unstable feedback loop, resulting in an oscillation at the output.'...
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### Using a single resistor for constant current load

I have a super capacitor (1000F) laying around and I want to measure ESR and it's capacitance. I have access to a 8V/500A power supply and various meters. If I wanted to charge/discharge the ...
1 vote
260 views

### Surface mount capacitor value confirmation

I was just checking for some bad caps on my TV as I get a large distortion for a few minutes at power up. The power board looked fine but I noticed some aluminium surface mount caps were bulging ...
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### What equivalent series resistance (ESR) capacitor should I replace bad one with?

I've got a bad clock capacitor in my original xbox that I'm trying to replace. It's a 1F 2.5V cap however, I'm not sure what Equivalent Series Resistance (ESR) the new cap should be. I see they sell 1 ...
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