Author Topic: Counterfit Parts  (Read 2299 times)

Offline alan sailer

  • High Voltage Engineer
  • ****
  • Posts: 258
  • Karma: +17/-1
    • View Profile
Counterfit Parts
« on: July 07, 2021, 03:59:08 AM »
A friend of mine is also interested in electronics and really enjoys getting a deal. He wanted some IRFP260 devices
for a project and bought some at a great price off Ebay. From China. Two sets from different vendors.

He suspected that the parts were not right and gave them to me to get X-rayed at work. The machine was down
so he had to wait.

A few days ago I looked up how to dissolve the epoxy casing on chips and it sounded fun. Concentrated sulfuric acid at 200C.

Today I got done with the last device of three and the results were interesting.

The real IRFP260 from a real vendor measured 5.1nF. The die was 58500mils^2. (that's thousandths of an inch square).

The first fake 260 was 1.3nF and 18000mils^2.

The second was 0.84nF and 9800mils^2.

The prices he paid were 0.8$, 1$ and 2.50$. So even the lower priced parts were not a deal percentage wise.

To first order the capacitance and the die area tracks nicely. Another feature was the heat-sink. The fake parts had metal
that was much thinner and smaller in area. Although all three metal tabs were copper.

I know that fake parts is not a new concept around these forums. But it was still sort of interesting to see haw really bad
it can get. I can only hope none of this crap ends up in anything important.

I also find it depressing that people are actually spending time and ingenuity making and selling such sad scrap. It makes
me glad that my career was on the up and up. I never lied to ship a part.

Cheers.
« Last Edit: July 07, 2021, 04:02:59 AM by alan sailer »

Offline MRMILSTAR

  • High Voltage Senior
  • *****
  • Posts: 535
  • Karma: +20/-0
  • Cedar Rapids, Iowa
    • View Profile
Re: Counterfit Parts
« Reply #1 on: July 07, 2021, 05:21:54 AM »
I've reached the point where I won't buy any active electronic devices from China. there are just way too many fakes. The ones that I have had success with are high voltage diodes but that's as far as I will go. Any sort of transistors I will only buy from US suppliers.
« Last Edit: July 07, 2021, 10:39:13 PM by MRMILSTAR »
Steve White
Cedar Rapids, Iowa
Retired electrical engineer

Offline futurist

  • Global Moderator
  • High Voltage Engineer
  • *****
  • Posts: 203
  • Karma: +8/-0
    • View Profile
Re: Counterfit Parts
« Reply #2 on: July 07, 2021, 08:05:55 PM »
I had similar experience when I bought a bunch of 40N60 TO-247 IGBTs off ebay from china
I dissolved epoxy in conc. nitric acid, and revealed die was significantly different from genuine 40N60 which I got from Hydron, if I remember correctly they were ordered from farnell

I have photos somewhere, I'll post them if I find them. Did you make x-ray photos of the parts? It's much more convenient than decapping silicon with acid

Offline Mads Barnkob

  • Administrator
  • Executive Board Member
  • *****
  • Posts: 2267
  • Karma: +71/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: Counterfit Parts
« Reply #3 on: July 07, 2021, 09:23:06 PM »
Hydron wrote about buying 75N60's a while ago: https://highvoltageforum.net/index.php?topic=193.0
https://kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics
https://www.youtube.com/KaizerPowerElectronicsDk60/join - Please consider supporting the forum, websites and youtube channel!

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +14/-0
    • View Profile
Re: Counterfit Parts
« Reply #4 on: July 08, 2021, 12:00:16 AM »
Unfortunately TO-247 are imo the most faked components in this hobby. I think I've ordered from 20+ vendors in hoping to find one that actually works. Eventually I gave up and started ordering bricks/igbt modules, I have seen fakes but they're obvious with the lower price attached to them.

Offline alan sailer

  • High Voltage Engineer
  • ****
  • Posts: 258
  • Karma: +17/-1
    • View Profile
Re: Counterfit Parts
« Reply #5 on: July 08, 2021, 02:34:38 AM »
futurist,

I would have loved to do x-rays but the machine at work was broken. I basically did the acid because I was interested in getting the data.

Once again, this is not news to experienced people on this forum. It was just kind of fun for me.

On a side note I did buy some SKM100 form a Chinese source for my last project. They apparently work just fine. I'm not stressing them in
voltage but the current is 5.5X the maximum spec.

Cheers.

A side note: this post would not load until I tried again.

Offline Hydron

  • Administrator
  • High Voltage Engineer
  • *****
  • Posts: 487
  • Karma: +25/-0
    • View Profile
Re: Counterfit Parts
« Reply #6 on: July 08, 2021, 01:28:26 PM »
As mentioned in my post on aliexpress FGY75N60s, I think I was at a large advantage due to the fact that the IGBTs were one of the cheaper parts available in "Power TO247" packages in the first place, reducing the options for faking them by re-labelling the cheapest thing they could find (though it doesn't stop other methods of cheating, like making fake parts from scratch). That was also a few years back, situation could have changed significantly since.

Offline Hiemal

  • High Voltage Enthusiast
  • *
  • Posts: 7
  • Karma: +0/-0
    • View Profile
Re: Counterfit Parts
« Reply #7 on: September 29, 2021, 01:26:47 AM »
As a general rule, I don't buy any parts from aliexpress/ebay from china that still "work", in a sense that the part is still the basic component it claims to be. I.e. a MOSFET can still be a MOSFET, and appear to work, but is a completely different die inside the package.

Digital items that either work or don't are less suspect. Arduinos, micros, digital sensors, etc. The only thing you need to pay attention to is getting knockoffs, that still perform the same. Like, receiving a Gigadevice STM32 micro instead of a true ST part; it still does the same thing, but it's a knockoff.

There's also lcsc.com which lets you source chinese products reliably. I've purchased from them many times in the past and you always get exactly what you ordered, no counterfeits. Funny thing is you can actually order knockoff parts from them too!, and they're almost always better than the same knockoffs you'd buy from ebay or aliexpress.


Offline johnf

  • High Voltage Technician
  • ***
  • Posts: 192
  • Karma: +6/-0
    • View Profile
Re: Counterfit Parts
« Reply #8 on: September 29, 2021, 06:24:54 AM »
All they need to do is buy cheap lesser spec'ed overrun parts from a legit maker and remove the markings and put new laser marked part number on from an expensive part.
Measuring Gate capacitance is easy for Fets not so reassuring for IGBTs of course.
Once upon a time I worked for a very large electronics company and one line of products we made were 2 way radios (RT's) for trucking firms Taxis and law enforcement for worldwide sale.
We had several of our designs copied in an Asian country and sold at much cheaper prices worldwide. We then started making fake parts ourselves this involved a cmos 4013 all the markings taken off legs then bent around the other way and circuitry put around it to make it look like a well known Switch mode controller IC. WEe marked these ourselves with a commercial inkjet printer that used uv cure. You guessed it our design was copied and they were having terrible trouble making it go. It would not work with the unitrode part, they asked us for spares and we sold them a few hundred parts for many many terns of dollars each. Our vendor mark on our fake parts looked like the Signetics logo who never made items like tis

Offline futurist

  • Global Moderator
  • High Voltage Engineer
  • *****
  • Posts: 203
  • Karma: +8/-0
    • View Profile
Re: Counterfit Parts
« Reply #9 on: September 29, 2021, 02:02:50 PM »
Interesting story ;D

You reminded me of a similar story on local elektronika.ba website
Owner of the site designed nixie clock and wanted to sell kits on elecrow. He sent them the schematics, PCB design files and photos of the assembled clock but they wanted him to ship assembled clock to China so they can copy it. At the end he decided to sell PCBs only :D

https://www.elecrow.com/warm-tube-clock-v2-pcb-board-p-1154.html
https://www.elektronika.ba/forum/viewtopic.php?f=25&t=15843#p148842
« Last Edit: September 29, 2021, 02:13:30 PM by futurist »

High Voltage Forum

Re: Counterfit Parts
« Reply #9 on: September 29, 2021, 02:02:50 PM »

 


* Recent Topics and Posts

post Re: Big Coil Build Log
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
Today at 05:47:34 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
davekni
Today at 04:45:07 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
Today at 04:18:27 AM
post Push Pull VTTC
[Vacuum Tube Tesla Coils (VTTC)]
janno288
Today at 01:10:08 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 27, 2024, 10:54:52 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
markus
March 27, 2024, 11:53:42 AM
post Re: OCD Triggering Early + Low Output
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 27, 2024, 05:14:36 AM
post Re: Is the UD2.7C under voltage lock out basically worthless?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 27, 2024, 04:47:48 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 27, 2024, 04:41:59 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 27, 2024, 12:04:34 AM
post Re: Super flat QCW simulation (does this look reasonable?)
[Dual Resonant Solid State Tesla coils (DRSSTC)]
toooldforthis
March 26, 2024, 11:08:14 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 26, 2024, 11:07:20 PM
post Re: Is the UD2.7C under voltage lock out basically worthless?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 26, 2024, 10:46:29 PM
post OCD Triggering Early + Low Output
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Saattvik24
March 26, 2024, 09:03:43 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 26, 2024, 08:46:59 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 26, 2024, 05:02:18 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 26, 2024, 03:16:03 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
Anders Mikkelsen
March 26, 2024, 01:41:49 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 26, 2024, 04:48:22 AM
post Re: Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
MRMILSTAR
March 26, 2024, 04:16:37 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 26, 2024, 04:16:24 AM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
davekni
March 26, 2024, 04:13:02 AM
post Re: CM400 Induction Heater
[Electronic Circuits]
davekni
March 26, 2024, 04:00:43 AM
post Re: Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
davekni
March 26, 2024, 03:19:18 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
March 26, 2024, 01:50:42 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 25, 2024, 08:05:02 PM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
Mads Barnkob
March 25, 2024, 07:41:29 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 25, 2024, 06:45:46 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 25, 2024, 05:44:25 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
Anders Mikkelsen
March 25, 2024, 04:47:17 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 25, 2024, 04:27:22 PM
post Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
MRMILSTAR
March 25, 2024, 03:57:34 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
markus
March 25, 2024, 02:06:41 PM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
KrisPringle
March 25, 2024, 04:43:25 AM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
davekni
March 25, 2024, 02:39:40 AM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
KrisPringle
March 25, 2024, 12:47:09 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 24, 2024, 07:36:32 PM
post Re: My completed 14-stage Cockroft-Walton voltage multiplier
[Voltage Multipliers]
Alberto
March 24, 2024, 07:27:24 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 24, 2024, 04:25:23 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 10:47:35 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 09:30:21 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 04:34:31 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 03:04:25 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 01:38:34 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 04:20:03 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
davekni
March 23, 2024, 12:54:30 AM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
davekni
March 23, 2024, 12:05:57 AM
post capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 22, 2024, 11:45:03 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
OmGigaTron
March 22, 2024, 11:30:09 PM
post Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
Mads Barnkob
March 22, 2024, 10:20:35 PM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Benbmw
March 22, 2024, 09:21:13 PM
post Re: What actually kills MOSFETs?
[Beginners]
AstRii
March 22, 2024, 03:37:11 PM
post What actually kills MOSFETs?
[Beginners]
FPS
March 22, 2024, 05:09:20 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 22, 2024, 03:57:54 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 22, 2024, 02:59:25 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 21, 2024, 06:31:42 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
rikkitikkitavi
March 21, 2024, 03:08:01 PM
post Re: [WTS] IGBT, Ferrite, Capacitors, Tools, PSU, Industrial components and parts
[Sell / Buy / Trade]
Mads Barnkob
March 21, 2024, 01:37:32 PM
post Re: Difference between these transformers
[Transformer (Ferrite Core)]
Alberto
March 21, 2024, 11:42:07 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 21, 2024, 04:09:14 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 21, 2024, 02:15:31 AM
post My Homemade Structural Analysis X-Ray Machine
[X-ray]
Luca c.
March 21, 2024, 01:35:40 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Saattvik24
March 20, 2024, 10:40:00 PM
post Re: Difference between these transformers
[Transformer (Ferrite Core)]
Mads Barnkob
March 20, 2024, 08:03:41 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Mads Barnkob
March 20, 2024, 07:51:57 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 20, 2024, 10:39:47 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 20, 2024, 04:09:59 AM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 20, 2024, 01:13:23 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Keybored
March 20, 2024, 12:45:16 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 20, 2024, 12:30:30 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 19, 2024, 11:12:24 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 19, 2024, 09:47:49 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 19, 2024, 09:44:19 PM
post Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Saattvik24
March 19, 2024, 06:52:09 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 19, 2024, 05:02:44 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
Mads Barnkob
March 19, 2024, 05:01:41 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 19, 2024, 04:31:02 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 19, 2024, 03:59:54 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 19, 2024, 06:41:39 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
davekni
March 19, 2024, 04:05:49 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
OmGigaTron
March 18, 2024, 09:08:35 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
2020-Man
March 18, 2024, 09:07:35 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
Twospoons
March 18, 2024, 08:57:06 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
MRMILSTAR
March 18, 2024, 03:51:33 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 18, 2024, 02:59:46 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 18, 2024, 02:33:25 PM
post Can I Trust This Super Cheap Site?
[General Chat]
2020-Man
March 18, 2024, 11:02:12 AM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Twospoons
March 18, 2024, 02:36:11 AM
post Re: Best forum for vacuum tube amplifiers?
[General Chat]
Mads Barnkob
March 17, 2024, 07:42:55 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 04:15:14 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 05:05:04 AM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
davekni
March 17, 2024, 04:50:51 AM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Twospoons
March 17, 2024, 04:45:17 AM
post 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 04:17:51 AM
post Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Terry
March 17, 2024, 01:29:32 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 17, 2024, 12:33:06 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Keybored
March 16, 2024, 08:46:20 PM
post Re: Bleeder resistor for MMC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Hydron
March 16, 2024, 08:39:24 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Hydron
March 16, 2024, 08:21:44 PM
post Best forum for vacuum tube amplifiers?
[General Chat]
yourboi
March 16, 2024, 08:20:13 PM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal