i ramdomly broke my mosfet by tin some solder on it.

gunoru

New Member
OP
Newbie
Joined
May 11, 2024
Messages
3
Trophies
0
Age
35
XP
24
Country
Thailand
I got 30 IRH8343 (as recommended in the Picofly manual) MOSFETs on AliExpress.

I decided to use them.
Initially, the D and G were insulated as they should be for MOSFETs.

But after tinning them with some solder, they seemed to begin breaking since the D and G are now short-circuiting with some resistance (25 to 1.25 k ohms).

Now, I've broken 10 out of 15.

Does anyone have an idea of what's going on?
 

Attachments

  • IMG_20240511_144000.jpg
    IMG_20240511_144000.jpg
    2.2 MB · Views: 4

urherenow

Well-Known Member
Member
Joined
Mar 8, 2009
Messages
4,814
Trophies
2
Age
48
Location
Japan
XP
3,734
Country
United States
a MOSFET, no matter how many pins it has, has 3 important things: Source, Drain, and Gate. If it has more than 3 pins, then there are multiple source and/or drain pins. As long as the pins that are shorted are of the same type (but there is usually only 1Gate pin), then the short does no harm at all. Many installers will short the multiples on purpose, even. If you're measuring before tinning, and getting these results after tinning and before trying to solder it to the board, then I have to question the type of solder you're using and how much heat, as well as exactly what you're doing/using to hold them steady. Simply tinning anything shouldn't break it. Even if you shorted it, but never pushed a meaningful amount of current through it. And it's super easy to fix a bridge. But... 25 to 1.25k ohms is definitely NOT a short. Less than 1 ohm is a short.

The first thing you should do before using a meter on a MOSFET, is to short the Gate and Drain pins. THEN you can check continuity between Source (black probe) and Drain (Red probe), and it should give you an OL. If you leave the black probe on source, then touch the GATE pin with the red, and move it back to the Drain pin, you will have some sort of continuity. That means it's good, not broken.
 
Last edited by urherenow,
  • Like
Reactions: emcintosh

gunoru

New Member
OP
Newbie
Joined
May 11, 2024
Messages
3
Trophies
0
Age
35
XP
24
Country
Thailand
a MOSFET, no matter how many pins it has, has 3 important things: Source, Drain, and Gate. If it has more than 3 pins, then there are multiple source and/or drain pins. As long as the pins that are shorted are of the same type (but there is usually only 1Gate pin), then the short does no harm at all. Many installers will short the multiples on purpose, even. If you're measuring before tinning, and getting these results after tinning and before trying to solder it to the board, then I have to question the type of solder you're using and how much heat, as well as exactly what you're doing/using to hold them steady. Simply tinning anything shouldn't break it. Even if you shorted it, but never pushed a meaningful amount of current through it. And it's super easy to fix a bridge. But... 25 to 1.25k ohms is definitely NOT a short. Less than 1 ohm is a short.

The first thing you should do before using a meter on a MOSFET, is to short the Gate and Drain pins. THEN you can check continuity between Source (black probe) and Drain (Red probe), and it should give you an OL. If you leave the black probe on source, then touch the GATE pin with the red, and move it back to the Drain pin, you will have some sort of continuity. That means it's good, not broken.
thakyou sir i will try to understand what you say with a time.

now i have to recheck my mosfet again.
this may issue about charged/discharge.

fyi.
i use 220 degree with normal 60/40 tinlead
solder wire. the real temperature is as small as it can meal.
 

Site & Scene News

Popular threads in this forum

General chit-chat
Help Users
  • No one is chatting at the moment.
  • a_username_that_is_cool @ a_username_that_is_cool:
    DDDS . Dual Developer Dedede System :)
    +1
  • BakerMan @ BakerMan:
    also happy birthday @Xdqwerty
    +1
  • BigOnYa @ BigOnYa:
    Is it me you're looking for?
  • MysticStarlight @ MysticStarlight:
    'Cause I wonder where you are
  • MysticStarlight @ MysticStarlight:
    wait I got the lyrics mixed up
    +1
  • BigOnYa @ BigOnYa:
    And I wonder what you do...Lol
  • BigOnYa @ BigOnYa:
    Its all good, I'm here to talk to you.
  • BigOnYa @ BigOnYa:
    Hello
  • BigOnYa @ BigOnYa:
    I've been playing fallout4 all day, I went into a elevator and it kept going, never stopped, waited 5 minutes, must of been a bug. How bout you, whatcha do today?
    +1
  • MysticStarlight @ MysticStarlight:
    I'm wondering why a stray tuxedo cat has a cloudy eye
  • MysticStarlight @ MysticStarlight:
    I've been playing TOTK all day also
    +1
  • MysticStarlight @ MysticStarlight:
    Oh you reminded me of those elevator nightmares
  • BigOnYa @ BigOnYa:
    Awesome game, fun how they force you to build, but you can build as you want
  • MysticStarlight @ MysticStarlight:
    It is super fun, I actually prefer it over BoTW
    +1
  • BigOnYa @ BigOnYa:
    The guy holding the sign always cracked me up, esp when you fail, and it falls
  • MysticStarlight @ MysticStarlight:
    Ah yes, that guy lol. I still need to find all his signs. The game has a lot to do though so I don't know what to finish first
  • MysticStarlight @ MysticStarlight:
    I'm 120 hours in and am still like 44.4% done
    +1
  • BigOnYa @ BigOnYa:
    Good times. Building is starting to get good around now for you. You making me want to make run thru again.
  • BigOnYa @ BigOnYa:
    Ok good chatting, enjoy your gaming, and avoid the lightning, or put your sword away. Good night.
  • K3Nv2 @ K3Nv2:
    All I gotta do is not spend $10 in the next 5 days and I'll break even this month lol
  • K3Nv2 @ K3Nv2:
    @BigOnYa, tell your wife not to forget her wallet
    +1
    K3Nv2 @ K3Nv2: https://youtu.be/YMAa6obDNZs?si=rymChLKeTdyS8nqk