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Products => Test Equipment => Topic started by: BirdManPhil on May 20, 2024, 02:48:08 am

Title: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: BirdManPhil on May 20, 2024, 02:48:08 am
Ive been doing a ton of board work on cel phones and tablets over the past couple years and I've gotten by with my cheap $30 Chinese dmm, and my more expensive 5.5 digit Hantek bench dmm. 
Bith meters are very sluggish in continuity (beep) mode. Neither Meter has any lcr functions but can guestimate capacitance roughly.
I am looking to up my game alot this summer by obtaining a high quality accurate dmm and also an lcr meter.

I'd like a dmm or lcr meter that can accurately measure the teeny tiny caps on iphone logic boards for example, as well as provide almost immediate audible alerts when using beep mode. I can't stand how long i have to wait for my meters to register continuity.

Separate continuity/ohm/diode modes are a must.

High voltage and high current abilities aren't necessary at all. I'm more concerned with the accuracy of low voltage, low resistance and low capacitance measurements as well as responsiveness.
Data logging and or pc interface is also nice but not 100% necessary

I am looking at a few different fluke handheld dmms as well as a few lcr meters.
I might grab 2 lcr meters, the shannon st42 tweezers and a de-5000

Any advice or dmm recommendations would be appreciated tyvm.


Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: tautech on May 20, 2024, 02:56:08 am
Ive been doing a ton of board work on cel phones and tablets over the past couple years and I've gotten by with my cheap $30 Chinese dmm, and my more expensive 5.5 digit Hantek bench dmm. 
Bith meters are very sluggish in continuity (beep) mode. Neither Meter has any lcr functions but can guestimate capacitance roughly.
I am looking to up my game alot this summer by obtaining a high quality accurate dmm and also an lcr meter.

I'd like a dmm or lcr meter that can accurately measure the teeny tiny caps on iphone logic boards for example, as well as provide almost immediate audible alerts when using beep mode. I can't stand how long i have to wait for my meters to register continuity.

Separate continuity/ohm/diode modes are a must.

High voltage and high current abilities aren't necessary at all. I'm more concerned with the accuracy of low voltage, low resistance and low capacitance measurements as well as responsiveness.
Data logging and or pc interface is also nice but not 100% necessary

I am looking at a few different fluke handheld dmms as well as a few lcr meters.
I might grab 2 lcr meters, the shannon st42 tweezers and a de-5000

Any advice or dmm recommendations would be appreciated tyvm.
Welcome to the forum.

IMO you need skip any thoughts of DMM's for fine SMD work and get proper SMD smart tweezers that provide very fast readings and a pile of features.
I highly recommend these from member Shannon:
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/ (https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/)

AliExpress listing:
https://www.aliexpress.com/item/1005004239869204.html? (https://www.aliexpress.com/item/1005004239869204.html?)
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: KungFuJosh on May 20, 2024, 03:21:37 am
+1 for the Shannon ST42 tweezers. They're fantastic. If you want something truly better, you'll need to spend at least 10 times as much on a bench meter. If budget isn't an issue, than get yourself the Shannon tweezers, and a Sourcetronic ST2830 or ST2832. You can get tweezers that attach to the LCR bench meters, but even that attachment will cost as much as the Shannon tweezers if you don't buy generic.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: indman on May 20, 2024, 06:34:37 am
I am looking at a few different fluke handheld dmms as well as a few lcr meters.
I might grab 2 lcr meters, the shannon st42 tweezers and a de-5000
Any advice or dmm recommendations would be appreciated tyvm.
Pay attention to this device - it will good replace all the other lcr meters you have listed before  ;)
https://www.amazon.com/stores/LCR-Reader/LCR-Reader/page/BBF0E19C-D5B7-4E73-AF3A-DFC2CFC8923C (https://www.amazon.com/stores/LCR-Reader/LCR-Reader/page/BBF0E19C-D5B7-4E73-AF3A-DFC2CFC8923C)
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: EEVblog on May 20, 2024, 08:40:47 am
Ive been doing a ton of board work on cel phones and tablets over the past couple years

Whatever you get, get some super fine precision meter leads like these:
https://www.amazon.com/POMONA-6342-TEST-PROBE-SET/dp/B0026GV3A2 (https://www.amazon.com/POMONA-6342-TEST-PROBE-SET/dp/B0026GV3A2)
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: armandine2 on May 23, 2024, 08:40:53 pm
Pomona 6342 - Small size is good, but not sure I like these lightly sprung probe tips -  :palm:
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: shapirus on May 23, 2024, 10:20:59 pm
IMO you need skip any thoughts of DMM's for fine SMD work and get proper SMD smart tweezers that provide very fast readings and a pile of features.
But a DMM is still needed for continuity testing and voltage measurements. LCR tweezers won't do it.

Speaking of that, there's been a ton of threads and posts specifically regarding the continuity buzzer response speed. Brymens (maybe not all) are good. Same with Flukes. At least some Uni-T meters are also very fast in that.

Another important parameter to watch out for is autoranging speed. Slow autoranging is just as annoying as slow continuity response.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: thm_w on May 23, 2024, 11:25:12 pm
https://www.eevblog.com/forum/testgear/multimeter-with-continuity-test-buzzer-that-responds-immediately/ (https://www.eevblog.com/forum/testgear/multimeter-with-continuity-test-buzzer-that-responds-immediately/)
https://docs.google.com/spreadsheets/d/1cXzYpIoyVm9QJUju4KXqM22CEQZP3_xwWvDyeVwxTy4/edit#gid=570637604 (https://docs.google.com/spreadsheets/d/1cXzYpIoyVm9QJUju4KXqM22CEQZP3_xwWvDyeVwxTy4/edit#gid=570637604)
https://lygte-info.dk/info/DMMReviews.html (https://lygte-info.dk/info/DMMReviews.html) (you have to click on each meter review then search for continuity time measured)

Brymen 829 (<5ms) should be good? But there are many others.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: tautech on May 23, 2024, 11:50:43 pm
IMO you need skip any thoughts of DMM's for fine SMD work and get proper SMD smart tweezers that provide very fast readings and a pile of features.
But a DMM is still needed for continuity testing and voltage measurements. LCR tweezers won't do it.
Yeah well my now retired ST3 smart tweezers had a graphing mode capable of 8V but not sure what the latest ST* versions offer.
Never used it as any slipup would possibly wreck a very valuable tool that even 15 yrs ago cost more than I've spent on all DMM's since.

Quote
Another important parameter to watch out for is autoranging speed. Slow autoranging is just as annoying as slow continuity response.
WRT the great ST42, a buddy tried it out against his $ $ Agilent LCR meter the other day and was shocked at the measurement speed and precision.
Immediately said to get one for him.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: EEVblog on May 24, 2024, 12:28:45 am
Pomona 6342 - Small size is good, but not sure I like these lightly sprung probe tips -  :palm:

Yeah, they could be firmer.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: shapirus on May 24, 2024, 07:57:31 am
Quote
Another important parameter to watch out for is autoranging speed. Slow autoranging is just as annoying as slow continuity response.
WRT the great ST42, a buddy tried it out against his $ $ Agilent LCR meter the other day and was shocked at the measurement speed and precision.
Immediately said to get one for him.
Yeah, I meant DMMs in that context. I have the ST42 myself. Great tool, and yes, autoranging is very fast indeed.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: BirdManPhil on May 24, 2024, 10:28:28 pm
Can I buy these in the US I can't use aliexpres they force delivery with speedx who steals packages
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: tautech on May 24, 2024, 10:43:01 pm
Can I buy these in the US I can't use aliexpres they force delivery with speedx who steals packages
ST42 ?

Jump into the ST42 thread and ask Shannon if he has a US reseller:
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/ (https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/)
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: 2N3055 on May 24, 2024, 10:52:47 pm
Pomona 6342 - Small size is good, but not sure I like these lightly sprung probe tips -  :palm:

Yeah, they could be firmer.

I like ProbeMaster fine tip probes miles better than that Pomona..

For Pomona I got tip kit that includes solid needles too.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: thm_w on May 24, 2024, 11:21:32 pm
Can I buy these in the US I can't use aliexpres they force delivery with speedx who steals packages

Click on the delivery options on the right side.. They give you three options, two are aliexpress.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: Kean on May 25, 2024, 01:15:20 pm
For Pomona I got tip kit that includes solid needles too.

Instead of Pomona 6342, I have bought a few sets of Pomona 6275.  These have the solid stainless tips (quite sharp) instead of the gold pogo spring tips.

I still have to occasionally squeeze the sockets in the handpieces a touch to tighten them up, but I find the smaller probes more convenient.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: 2N3055 on May 25, 2024, 02:03:56 pm
For Pomona I got tip kit that includes solid needles too.

Instead of Pomona 6342, I have bought a few sets of Pomona 6275.  These have the solid stainless tips (quite sharp) instead of the gold pogo spring tips.

I still have to occasionally squeeze the sockets in the handpieces a touch to tighten them up, but I find the smaller probes more convenient.

That is just a version of bundled combination of probes/tips. I have bought Probes 6342 and tip kit 6354.
Title: Re: Best DMM and LCR for small low voltage circuits ie cell phones and tablets
Post by: Kean on May 25, 2024, 02:11:28 pm
That is just a version of bundled combination of probes/tips. I have bought Probes 6342 and tip kit 6354.

Indeed, I should have mentioned the 6354 tip kit.  I bought one years ago, but found the only tips I continued to use from it were the solid stainless P/N 6213.
It costs almost as much as a new probe set, so not great value unless you will use more than one type or really want the "fancy" multi-point pogo-pins (aka P75-Q1/Q2 I think).