How to choose a LCR Meter

diy lcr meter

Hi everyone,
I want to buy an LCR meter, I am a young SMPS engeneer and I want to test the transformer, inductor and capacitor I am using, my switcher are operating from 20K up to 1MHz. I also like to construct guitar and power amp, so I want to check the impedance of my pickups and speaker and if possible trace the impedance curve (on PC).
What kind of LCR meter do I need ?
Does it have to go from 20Hz up to 1MHz? (is the component be test at is operating frequency?)
Because the SMPS are high power, I need the LCR meter to accept bias current ?

I would like if you could suggest me some model of LCR.

What do you think of the:
LCR-8101(Instek)
PM6306 (Fluke)
1910-1920 (Quadtech)
4284A (HP)

This LCR meter must accept a discret bias current source because, I don`t have the money to buy one (which is 6000.00$ and more)

P.S. I don`t really understand how a bias current source work, does it act as a sinusoidal source ?

What is the difference between a impedance analyser and a LCR meter ?

lcr meter

I don't want to comment all points, just a few remarks:

The bias current is always a DC signal, it can be used to check large signal properties as current dependant inductance or core saturation. But you shouldn't expect to see all parameters that are determining e.g. the large signal behaviour of a SMPS transformer.

To record the impedance characteristic of a speaker, an analyzer with an almost continuously variable frequency would be needed.

diy lcr

Thanks for the reply, that was what I tought, but when I looked at the bias current source, they would say in the spec 20Hz to XXHz
**broken link removed**
or
Precision 0-25A DC Bias Current Source with 3MHz Bandwidth

that must be the bandwith of the error amp

how to choose lcr meter

Nobody noes how to choose an LCR meter, characteristic, pro an con some model??

impedance meter schematic

I think it mainly depends on how much $$$ you want to spend on it !
for myself, I bought a DIY lcr meter for some 150 euros and I'm quite satisfied with it
I would have bought elektor lcr meter, but it is no more available, and with old components difficult to find.
Now I'm considering doing one other myself, looking for inspiration in the numerous russians lcr meters that you can find on the net.
there is another thread on this forum dealing with these meters :

inductivity bias current source

Anybody own a LCR meter on this forum ? These LCR meter schematic dosen`t seems to be high frequency. I am willing to put many thousand of dollard to buy a good LCR meter

lcr meter with variable frequency

I made my choice, I will buy the 1910 from quad tech, let me know if you have one, I would like to have feedback.
Thanks

Re: lcr meter with variable frequency

Like a previous poster mentioned, it all depends on the amount of money you have to spend and what bells and whistles you need. For my money, I use the 4263B Agilent LCR Meter.
Agilent | Select & Compare: Bench Top LCR & Resistance Meters
Good luck!

Not a problem purchasing an LCR meter, but you first just have to know how you expect the meter to be used. Actually the meter comes in two formats- Analog and Digital. The second one is costly as compared but provides much more accuracy. Most of the technicians use it to test frequencies from 100 to 10,000 Hz. Also it will check out your resistor, inductor or capacitor. Thanks

LCFesR 3.05 unit is a precise, wide range LCF and ESR meter that is to say it measures inductivity (L), capacity (C), frequency (F) and equivalent series resistance (ESR) of a capacitor inside an electronic circuit. The meter can be easily built with homemade one- or double-sided PCB and available electronic components. It's functions are base on an ATMega8-16PU or an improved ATMega88PA-PU microprocessor.

You can build one by following the project.

**broken link removed**

This paper reports capacitance measurement correlation between Direct Charge Measurement (DCM) and conventional LCR meter on 0.18um CMOS test structure. Measurement results of interconnect and MOSCAP test structures are presented. Mathematical analysis shows that DCM and LCR meter results correlate very well for MOSCAP as well. Amplitude Adjustment Method and Amplitude Extrapolation Methods are proposed to calibrate nonlinear C-V measurement errors. Theoretical discussion can also be applied to Charge-Based Capacitance Measurement (CBCM) because it uses similar stimulus.

There is an cheap but good enough LCR 2.9 bridge meter kit measuring L/C/R/Z/Rs/ESR/X/Q/D/Phase with 100Hz/1kHz/10kHz sine test signals found here: http://lcr.is-best.net/en/. May be you are interested in it.