⭐ Measurement of Capacitor ESR and Resonance Frequency with a VNA (Vector Network Analyzer)

Подписаться 986

Просмотров 7 тыс.

50% 1

In this video I describe how to measure capacitor ESR (Equivalent Series Resistance) and resonance frequency using a vector network analyzer. I show my homemade fixture, describe in detail how the measurements are made, demonstrate several examples, and show how to convert the S21 measurement to ESR. Any VNA that covers 100KHz to 1GHz can be used.
A printable version of the S21 to ESR conversion graph: chrisgrossman.com/yt/0012/VNA_...
A printable S21 to ESR conversion table: chrisgrossman.com/yt/0012/VNA_...
Here are the view graphs (including extra measurement examples) in pdf format: chrisgrossman.com/yt/0012/Shun...
Measuring Capacitor Parameters Using Vector Network Analyzers - An Electronics paper by Deniss Stepins, Gundars Asmanis, and Aivis Asmanis, describing full two port parameter measurement of capacitors . It claims the small inductance in series with the input and output ports only cause a small error: electronics.etfbl.net/journal...
Make Accurate Impedance Measurements Using a VNA - A Microwaves and RF article by Brian Walker of Copper Mountain Technologies describing component measurement techniques, their component measurement fixture, and their VNAs: www.clarke.com.au/pdf/CMT_Accu...
The sources of the ubiquitous white dog hair:
/ goberianblue
/ goberiananika
www.flickr.com/photos/divewiz...
Although I am a beta tester for Siglent SVA firmware, I receive no compensation. The Siglent test gear I own was bought and paid for with my money. I even paid for the VNA option on the SVA1015X which is now included for free.

Наука

Опубликовано:

24 июн 2020

Ссылка:

Скачать:

Готовим ссылку...

Добавить в:

Мой плейлист

Посмотреть позже

Комментарии : 36

@CodeJeffo 3 года назад

Very nice explanation & demonstrations! Thank you for sharing your knowledge, please continue to do so.

@poormanselectronicsbench2021 2 года назад

Thank you for sharing info for a relatively low cost and effort test rig for capacitors. This setup shuld work well for troubleshooting marginal components in a RF oscillator circuit ( tested out of circuit of course) as well as your intended ESR measurement function.

@CDN_Torsten 4 года назад

Excellent video - thanks Chris!

@Chris_Grossman 4 года назад

I hope it was helpful for you.

@silvanocalza8180 4 года назад

Thanks Chris for sharing this interesting video

@Chris_Grossman 4 года назад

You're welcome

@seamusdemora5598 3 года назад

This is great! Here's a suggestion for your next video: Show how to determine the value of a capacitor given an inductance of known value and using the VNA to find the resonant frequency. From there, speculate on how to make this measurement with a PIC micro :)

@AllElectronicsChannel 3 года назад

Great! I did not expected the response of the resistor rising at so lower frequency.. I used two resistors to mod an osciloscope broke 50 ohm input and in my tests the response was equal to the other original channel up to 350meg.

@rfmanchannel6915 4 года назад

Great job!!

@Chris_Grossman 4 года назад

Thank you

@joeshmoe7899 2 года назад

Just measured esr, in circuit, on S11 in series, with nanovna.

@chris_lynch 2 года назад

Great video, thankyou. The datasheet lists the VNA frequency range as 10Mhz to 1GHz but you are doing a sweep from 100kHz. I'm tempted to get one but 10MHz is restrictive. Is there a way to enable 100kHz?

@ewrokirill2023 Год назад

Hi! How to detect a short-circuited coil in a choke with NanoVNA? Thank you!

@grantcoward7716 4 года назад

Love your SVA presentations ! Not being a mathematician I can't work out how you arrive at a capacitance value given the ESR. Could you elaborate on the calculation for the 0.1uF example in your presentation so a simple soul can understand what is going on? Many thanks.

@Chris_Grossman 4 года назад

My next video will be how to measure the impedance, capacitance, and correct for fixture parasitics.

@TheDawinci 6 месяцев назад

Can you measure Elkos ESR at 100kHz with the VNA? It's out the same like a dedicated ESR meter?

@koceilaaizel6263 3 года назад

Thanks for the interesting video. Do you think it would be possible to measure extremely small capacitance such as femtofarad or even lower?

@Chris_Grossman 3 года назад

Not as I have shown. The problem is the parasitic capacitance from any fixture or probes will preclude accurate measurements. In my experience you can typically measure down to 10pF, if you are very careful about minimizing fixture/probe parasitics and do a good cal you can get down just below 1pF. If you are measuring on-chip devices on a IC wafer in a well designed test structure, have on-wafer calibration structures, GSG RF probes, and a very accurate network analyzer that goes high enough in frequency (into the GHz region) you can get believable measurements down to ~10fF and less accurate measurements down to about 1fF

@koceilaaizel6263 3 года назад

@@Chris_Grossman Thanks very much for your reply. And how much do you think such accurate network analyser would cost?

@johnwest7993 9 месяцев назад

I'd put a wire jumper between the test fixture pins to do my 'through' cal.

@Chris_Grossman 9 месяцев назад

The trough wire is part of the fixture. The shunt measurement is from the through to ground.

@Nf6xNet Год назад

Upvoted for the ubiquitous dog hair.

@davidsenabrealbujer 2 года назад

Hello. Great video and explanation! I'm amazed with you being able to sweep from as low as 100 kHz. The analyzer's datasheet states a range of 10 MHz-1.5Ghz. Did you do anything special to enable going as low as 100 kHz? Or is it a datasheet errata? Thank you!

@Chris_Grossman 2 года назад

The main frequency limitation is on the input directional coupler used to measure S11. It is not happy below 10 MHz. However S21 works well down to 1 MHz and is usable down to 100 KHz.

@davidsenabrealbujer 2 года назад

@@Chris_Grossman Thank you very much! 1 MHz... interesting... The tracking generator (according to datasheet) works from 5 MHz up. Have tried to go down to 1 MHz?

@andrewkurtz6280 2 года назад

Very helpful. Where can I get the chart and/or your equation for ESR?

@Chris_Grossman 2 года назад

Expand the video description comments above which are just below the video. All of the links are there.

@andrewkurtz6280 2 года назад

@@Chris_Grossman Thanks! It took a while to figure out how to find it...

@GigglingGobby 3 года назад

Do you have some updated links for the ESR conversion table and graphs please? The links provided seem to be unavailble now. Thanks for a very interesting video!

@GigglingGobby 3 года назад

Replying to myself, hehehe, it's ok, I used your formula at timestamp 10:34 to make a spreadsheet and now I can see any value I want, and the graph at that timestamp is the one I was after anyway. Job done :o)

@Chris_Grossman 3 года назад

The links work. Try again.

@GigglingGobby 3 года назад

@@Chris_Grossman The website chrisgrossman.com simply doesn't respond, whatever browser I use, it just times out. Maybe you can see it from within your network, or maybe you have a cached copy on your machine, but it doesn't seem to be accessible from the web. I've built my own spreadsheet for it now, but anyone else wanting to access the link may run into the same problem I'm seeing from here.

@Chris_Grossman 3 года назад

@@GigglingGobby it works from my cell phone on the cell network. I logged into another server in a remote facility and it works from there. I tried it using a VPN and it works. I tried using multiple browsers on both Linux and windows systems and all work. I checked the log and I can see it serving content.

@GigglingGobby 3 года назад

@@Chris_Grossman Thanks for testing that. I tried 4 browsers on 2 machines, and then with my mobile phone on Wifi on the same landline broadband and then with WiFi disconnected so I was using a completely different (mobile) ISP, still nothing. However, a couple of my friends managed to see your website, so I tried again but this time with VPN so it would look to the server like I was in another country and it instantly connected! Something's stopping my landline's and mobile's IP addresses (in the UK) from accessing the server where the website is hosted. No idea what's going on there, but I got there in the end :o)

@amirb715 3 года назад

one thing that people keep ignoring, including this video, is that ESR is NOT an actual physical resistor and its value is highly frequency dependent. So with this method you are ONLY calculating the ESR at that resonant frequency which is not that useful specially when it comes to electrolytics and their application which is normally low pass filtering at low frequencies.