Inside the new Keithley DMM7510 7.5 Digit Bench Multimeter
What gives this unit it's superb 16ppm/1year accuracy specification?
What construction techniques have they used?
How and why are Fluke so heavily involved?
What considerations are given to the power supply and isolation aspects?
How does it compare with the cheaper Keysight 34770A meter?
UPDATE: The ADC used is a custom 32bit one for slow reading, and an 18bit AD7982 for faster readings. This chip is not marked, and there appears to be two of them on board.
Forum: http://www.eevblog.com/forum/blog/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/'>http://www.eevblog.com/forum/blog/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/
The Precision Thin Film Resistor Network video: https://www.youtube.com/watch?v=Rxy-VpSDPg4
Hi-Res teardown photos: http://www.eevblog.com/2015/04/09/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/'>http://www.eevblog.com/2015/04/09/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/
Datasheets:
AD7982 18bit ADC: http://www.analog.com/media/en/technical-documentation/data-sheets/AD7982.pdf
LTC1050: http://www.linear.com/product/LTC1050
ISL28110: http://www.intersil.com/en/products/amplifiers-and-buffers/all-amplifiers/amplifiers/ISL28110.html
LSK389 Ultra low noise matched JFET http://www.linearsystems.com/assets/media/file/datasheets/LSK389.pdf
SSM2212 Dual matched transistor: http://www.analog.com/media/en/technical-documentation/data-sheets/SSM2212.pdf
DG411 Precision analog switch: http://www.vishay.com/docs/70050/dg411.pdf
TPS65251 Triple Switcher: http://www.ti.com/product/tps65251
Freescale MPC5125 Processor: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPC5125
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What gives this unit it's superb 16ppm/1year accuracy specification?
What construction techniques have they used?
How and why are Fluke so heavily involved?
What considerations are given to the power supply and isolation aspects?
How does it compare with the cheaper Keysight 34770A meter?
UPDATE: The ADC used is a custom 32bit one for slow reading, and an 18bit AD7982 for faster readings. This chip is not marked, and there appears to be two of them on board.
Forum: http://www.eevblog.com/forum/blog/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/'>http://www.eevblog.com/forum/blog/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/
The Precision Thin Film Resistor Network video: https://www.youtube.com/watch?v=Rxy-VpSDPg4
Hi-Res teardown photos: http://www.eevblog.com/2015/04/09/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/'>http://www.eevblog.com/2015/04/09/eevblog-731-keithley-dmm7510-7-5-digit-multimeter-teardown/
Datasheets:
AD7982 18bit ADC: http://www.analog.com/media/en/technical-documentation/data-sheets/AD7982.pdf
LTC1050: http://www.linear.com/product/LTC1050
ISL28110: http://www.intersil.com/en/products/amplifiers-and-buffers/all-amplifiers/amplifiers/ISL28110.html
LSK389 Ultra low noise matched JFET http://www.linearsystems.com/assets/media/file/datasheets/LSK389.pdf
SSM2212 Dual matched transistor: http://www.analog.com/media/en/technical-documentation/data-sheets/SSM2212.pdf
DG411 Precision analog switch: http://www.vishay.com/docs/70050/dg411.pdf
TPS65251 Triple Switcher: http://www.ti.com/product/tps65251
Freescale MPC5125 Processor: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPC5125
EEVblog Main Web Site: http://www.eevblog.com
The 2nd EEVblog Channel: http://www.youtube.com/EEVblog2
Support the EEVblog through Patreon!
http://www.patreon.com/eevblog
EEVblog Amazon Store (Dave gets a cut):
http://astore.amazon.com/eevblogstore-20
Donations:
http://www.eevblog.com/donations/
Projects:
http://www.eevblog.com/projects/
Electronics Info Wiki:
http://www.eevblog.com/wiki/
Done.
The pci connector is a pcie x4 connector
un multimetro que nunca tendre odio ser pobre jaja
Did anybody else notice just about all the axial resistors are mil-spec? Not particularly expensive parts, but I'd bet they're individually tested for low drift. It all goes into the high price tag; even in China that kind of labor doesn't come cheap.
A fan? In another video you showed why you don’t want a fan: to stabilize and equalize temp gradients on a board of a ppm-range instrument.
made in china
That type of transformer made up from ferrite tubes, coax and enamelled wire is very common in RF transmitters and very efficient!. In this instrument they probably use it, as you mentioned, as a synchronised DC/DC converter running at a few MHz. And don't be fooled by the 0 Ohm between the input measurement ground and the coax screen: even that screen is part of the transformer. So by exciting the primary winding formed by the inner conductor of the coax loops, you can have two isolated secondary voltages: one from the coax screen and the other from the enamelled wire winding.
Yeah but did you have to send it back after tearing it down?
"Made in China"
the list price for that little ltz1000 ? $468.22!!!!!
It’s like the kid that won’t sit still! Makes me tired just looking at it
Damn hold on let me get some privacy going here on my privet chair, with a paper towel roll next to me. OK I am going to watch this all the way to the end. Oh yaaaaaaa. what, what was that "made in China" man, man don't you know I am in good place right now. don't do that to me.
I'm waiting for a Keithley DMM6500 teardown video on EEVBlog
Any updates in 2021? Is it still the ultimate DMM for ultra low currents? I am looking for something measuring uAmps in 100mA range like the 7510, but maybe it can be done cheaper now?
but… I don't undersant how a thing like this cost lets way 3000€ and a old 6 1/5 dmm from the 70-70-90 cost SH something like triple the money.
Those gulps of salivea…
Thank you very much for this review, it is really well explained and described.
It helped me to choose between this one and the Agilent 34470A
My choice is KEITHLEY 7510
Maybe in 20 years from now, if the thing is still going or if they ARE even fixable, I can afford one!
It looks like that Fluke-commissioned component sits on a knockout board, given the cuts and four linkage points. I wonder why it appears to be removable.
can it measure my luck in winning the lottery?