Author Topic: Impossibly cheap Chinese breakout boards / parts  (Read 4478 times)

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Offline DavidJRobertsonTopic starter

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Impossibly cheap Chinese breakout boards / parts
« on: January 08, 2019, 12:07:04 pm »
I've been looking at a handful of pricey Analog Devices parts for a new project. One thing I don't understand is how it's possible to buy dev/breakout boards with these parts on eBay from China for far less than the cost of the chip alone.

Some examples (Pricing compared to RS, but it isn't the case that RS is unusually expensive here):

AD9959 4-channel DDS, 500MSPS
Available on a nice little board on eBay for £23 delivered, but costs £45 each excluding VAT in a tray of 260 from RS.

AD9850 1-channel DDS, 125MSPS
Available on a slightly-naff breakout board (which I wish had the output on an SMA connector) for £11 from eBay, but costs £21 each excl. VAT from RS.

AD831 RF mixer
Available on a nice board from eBay for £5, but costs £12 excl. VAT from RS.

AD8302 gain/phase detector
Available on a board from eBay for £4, but costs £20 excl. VAT from RS.


Are these counterfeit parts? Even if they are fake, they do still work just fine.... where can I buy them for these prices? Short of just buying the eBay boards and desoldering the parts, of course.

 

Offline metrologist

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #1 on: January 08, 2019, 05:06:03 pm »
That's a nice looking module that I should pick one up. I recall this discussion before and it was speculated these (9850 at the time) were either counterfeit or factory leaks... There was also talk that one large Asian distributor may be involved in getting the price down and then piecing the distribution.
 

Offline ebclr

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #2 on: January 08, 2019, 06:54:56 pm »
"Are these counterfeit parts? Even if they are fake, they do still work just fine...."

Ta sauce will cost higher than the salad, I don't  believe they are fake, They are only bought on a country where they can profit with little margin, because does not need to p[ay insurance for liability on anything and huge Bonuses for CEO's and legal departments, Cutting all those things makes possible to sell at this prices.
 

Offline In Vacuo Veritas

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #3 on: January 08, 2019, 07:08:04 pm »
L9 looks like he's had enough of this and is leaving
 
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Offline SiliconWizard

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #4 on: January 08, 2019, 08:19:40 pm »
Of course there are contracts saying you can't resale the low price sourced parts to compete with distributors (...)

Yes, but even so, if the chips are not resold as is but sold as part of development/breakout boards, I guess they can sell the boards at whatever price they see fit, just like any product that would use those chips, without even infringing anything.


 

Offline Synthtech

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #5 on: January 08, 2019, 09:56:26 pm »
Looks like the Night Factory has been running full steam.
 

Offline coromonadalix

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #6 on: January 09, 2019, 01:12:59 am »
You have some dds generators kit on ebay up to 200 mhz with touchscreens ?
 

Offline SiliconWizard

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #7 on: January 09, 2019, 01:27:07 am »
You have some dds generators kit on ebay up to 200 mhz with touchscreens ?

Something like this: https://www.ebay.com/itm/New-AD9854-DDS-Signal-Generator-STM32-F103-Controller-Board-Touch-color-screen/183296169012

It's 300MSPS so you won't get signals up to 200MHz but that's close.

 

Offline Bud

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #8 on: January 09, 2019, 01:35:52 am »
That's a nice looking module that I should pick one up. I recall this discussion before and it was speculated these (9850 at the time) were either counterfeit or factory leaks... There was also talk that one large Asian distributor may be involved in getting the price down and then piecing the distribution.
Someone reported before it did not work properly and the wiring of the chip was weird.
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Offline metrologist

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #9 on: January 09, 2019, 03:27:06 pm »
That's a nice looking module that I should pick one up. I recall this discussion before and it was speculated these (9850 at the time) were either counterfeit or factory leaks... There was also talk that one large Asian distributor may be involved in getting the price down and then piecing the distribution.
Someone reported before it did not work properly and the wiring of the chip was weird.

I think I found that thread here and posted in it. I did not not find much else on this module. I read something about the AD9910 being a bit off too, but performance wise.

https://www.eevblog.com/forum/rf-microwave/ad9959-ebay-board-troubleshooting/

https://www.eevblog.com/forum/testgear/ad9910-dds-module-420m-1msps-highest-output-sampling-frequency-signal-generator/

I guess I could think about the feeltech again
 

Offline bd139

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #10 on: January 09, 2019, 03:32:09 pm »
Let’s just say that its not eBay that is cheap but RS is fucking expensive in low quantities.

I bought 10x AD8307 from aliexpress for £3. Or £10 each on RS.

If you want to see how stupid RS pricing is check out SOIC breakout boards.
« Last Edit: January 09, 2019, 03:34:03 pm by bd139 »
 

Offline coppercone2

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #11 on: January 10, 2019, 06:27:19 am »
it might not be tested or something. look at how many specs those dds have to meet.
 

Offline TrickyNekro

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #12 on: January 10, 2019, 04:30:07 pm »
Let’s just say that its not eBay that is cheap but RS is fucking expensive in low quantities.

I bought 10x AD8307 from aliexpress for £3. Or £10 each on RS.

If you want to see how stupid RS pricing is check out SOIC breakout boards.

And also ADI just sells ore expensive with distributors. ADI online store sells them at sometimes half the price than Mouser/DK for some DSPs I use.

Yup! Noticed it with Coilcraft and Microchip direct too, I can confirm!
Mouser and Digikey are really for prototyping if you can afford to produce very large volumes, they got staff and bills too to pay plus profits.
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Offline Bud

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #13 on: January 10, 2019, 05:06:44 pm »
You have to add cost of shipping and importation, often you end up on par with Digikey and other distributors, unless you buy in suficient quantities to offset those costs. Purely looking at the sticker price on the web is delusional when stuff needs to cross the border.
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Offline Bud

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #14 on: January 10, 2019, 05:33:25 pm »
It is $5.99 by which carrier?
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Offline Bud

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Re: Impossibly cheap Chinese breakout boards / parts
« Reply #15 on: January 10, 2019, 05:57:25 pm »
so that will not work for non-US destination. UPS will also slap additional fees like fuel surcharge. Garantee, the final delivery bill will be times higher. Never in my life i got anything from UPS for that cheap even within Canada.
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