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Black buck 5.5A reverse polarity fuse location

barthchris

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Well, apparently the fuse didn't protect the driver. Diode is fine, tested on my PS (one thing wife didn't pack away). I jumped the fuse with a small piece of solder wick and no dice. All solder connections are proper, not bridging other components. Not sure what fried, no obvious damage such as smell, , burned traces, holes in microcontroller package, etc. Oh well, you play you pay, that's the game here. Lol! I was impressed with the driver though, simple layout, nice features.
 



barthchris

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Selecting the right Schottky diode will reduce your loss by about a third. Another way to do the is to use a P channel MOSFET. Connect the drain to the positive terminal and the source to the positive input of your driver. If the SG breakdown voltage is high enough, you can just connect the gate to the negative terminal of the battery or driver input. Very easy and your losses will be very small in comparison to any diode. If you choose a MOSFET with too low a SG breakdown voltage, you can still get by with the addition of a Zener diode and a gate resistor.

Any specific MOSFET you would recommend? Just for ease of availability in parts bin preferably a TO-220 package..
 

paul1598419

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Hmmm. Try an FQP47P06, but you will have to add a small diode across the drain and source junctions. Any small rectifier should do. Connect the cathode to the source and just ground the gate. At 5.5 amps you should dissipate about 789 mW of power in the FET, which is very small considering the amount of power dissipated by any diode. Good luck.
 
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barthchris

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Hmmm. Try an FQP47P06, but you will have to add a small diode across the drain and source junctions. Any small rectifier should do. Connect the cathode to the source and just ground the drain. At 5.5 amps you should dissipate about 789 mW of power in the FET, which is very small considering the amount of power dissipated by any diode. Good luck.
Thanks, got dig through my "hoarded" parts., got probably a thousand or so various FETs to chose from, sure a FQP47P06 is in there somewhere.
Is it just me or do all you guys do a certain amount of parts "hoarding"? Il take a heat gun, hell, even hold it off the propane grill and heat the back side of a PCB to melt the solder, one tap and it rains components. Lol! Do the same with SMD parts but use flux and hot air, sometimes the oven when wife isnt around. Lol!!!
 

Alaskan

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The last time I built reverse polarity protection for a device, I used a Schottky diode, I donno why I called it a Germanium in that post. That driver is in effect that drawing, reverse polarity pulls too much current and blows the fuse. I used to collect a lot of parts like that myself, but most of that was sold by my ex-wife during a divorce in 2012, I had all of my parts stored away and she broke and and stole them, sold them to some guy who lists stuff on ebay as a part time job. Police wouldn't do a damn thing about it, said it was a domestic problem.
 

paul1598419

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It's amazing what women who claimed to love you will do to you on the way out. I have had that experience three times before I got the idea that marriage is not a healthy activity. At least for me.
 

paul1598419

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Thanks, got dig through my "hoarded" parts., got probably a thousand or so various FETs to chose from, sure a FQP47P06 is in there somewhere.
Is it just me or do all you guys do a certain amount of parts "hoarding"? Il take a heat gun, hell, even hold it off the propane grill and heat the back side of a PCB to melt the solder, one tap and it rains components. Lol! Do the same with SMD parts but use flux and hot air, sometimes the oven when wife isnt around. Lol!!!

I was just looking at this post and noticed a horrible typo. You should ground the gate, not the drain. Sorry for that. I changed it in my original post.
 

barthchris

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I was just looking at this post and noticed a horrible typo. You should ground the gate, not the drain. Sorry for that. I changed it in my original post.
No prob, havent even messed with it yet. Been too busy with other "issues".

As far as women there has to be a few good ones out there that don't hate our hobbies. Mines a middle school teacher, been married 15yrs. She was OK until kids, now an uptight nun that I avoid like the plague. I cringe when the phone rings. The freaking doctor thought it would be a good idea to give her Adderall for "low energy", she never said the low energy is the depressive phase of manic depression... Now has permanent full-blown mania and loves it, cleaning and packing everything. Throwing out things she deems unnecessary, including my stuff. My stuff is OFF LIMITS, this has been repeated multiple times!!! Redline has been crossed, my non-resetable fuse has blown (staying on topic;)). HIPPA laws prevent me from communicating with her Dr. She thinks it a wonder drug. WTH!! I actually printed out the divorce papers today.
 
  • Wow
Reactions: GSS

paul1598419

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You know that adderall is just amphetamines. It is rarely prescribed for anyone not suffering from ADHD. She sounds like your typical speed freak.

Edited for typo.
 
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barthchris

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You know that adderall is just amphetamines. It is rarely subscribed for anyone not suffering from ADHD. She sounds like your typical speed freak.
Yes, I know exactly what it is. Its her first time using it and absolutely loves it so yes, now a speed freak. BTW, just blew my diode. Freaking alligator clip from PS briefly disconnected and reconnected, got a nice LED now. Was thinking of the NUGM03 525 diode. Any opinion on that diode?
 

Alaskan

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Sorry for your diode, most of us have killed one or more, myself a few, M140 the most expensive so far, thankfully. I prefer the NDB7475 because it is sealed under a cap with a window, the NUGM03 uses an integrated ball lens which isn't always collimated to infinity causing the focus to be off one way or another, at least, one way which I believe is out (re: in-out). Without that cap, debris can get on the diode itself and cause a failure. Beyond that problem I am not sure if this diode suffers from being exposed to air, I know the NUBM07E has that problem and will have a shortened life when using it, just sitting without the ball lens in place doesn't appear to degrade the diode, but using it when exposed to air, yep.

Regarding relationships with women, at base, I often think we are just their banks, a source for money and support, and they are our bank for DNA to move forward into the future. Once you have children (and under the age of 18), they can leave you and still get support and your children will carry forward your DNA, deal is done for both.
 

paul1598419

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Good point on the green diode, Chris, but you have a typo. It should be the NDG7475, not NDB7475. On your diode, that is why I started using transistor sockets some time ago instead of alligator clips. You solder wires to the socket and connect those to your PS.
 

barthchris

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Sorry for your diode, most of us have killed one or more, myself a few, M140 the most expensive so far, thankfully. I prefer the NDB7475 because it is sealed under a cap with a window, the NUGM03 uses an integrated ball lens which isn't always collimated to infinity causing the focus to be off one way or another, at least, one way which I believe is out (re: in-out). Without that cap, debris can get on the diode itself and cause a failure. Beyond that problem I am not sure if this diode suffers from being exposed to air, I know the NUBM07E has that problem and will have a shortened life when using it, just sitting without the ball lens in place doesn't appear to degrade the diode, but using it when exposed to air, yep.

Regarding relationships with women, at base, I often think we are just their banks, a source for money and support, and they are our bank for DNA to move forward into the future. Once you have children (and under the age of 18), they can leave you and still get support and your children will carry forward your DNA, deal is done for both.

Good point, Ive decanned my fair share of diodes. Usually due to burning the window from debris. Im a lens changing fool, I try to take precautions but eventually it will happen. With these high power diodes, all it takes is a microsecond for the glass to melt. Of course, if anything falls on the facet its toast but I also wonder if the window tamps down COD creating back reflections. I don't think the can is filled with an inert gas.

I've had a version of that same DNA donor relationship theory for some time. Modern society, longer lifespans, social changes, etc has enabled and almost promoted this broken families.


Paul, thanks for the correction and the alligatorless connection tip. Im itching for a green diode.
 

barthchris

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<continues the derailing with glee>



Ok, update on the totally off topic Adderall. On Her second refill. I'm seriously thinking of packing my shit up in boxes and gettingTFO! Hell, she'll probably pack them for me not knowing my intentions. At least three to four hrs of cleaning every evening. Toothbrush to the grout type cleaning. Wow! Absolutely nuts! Tried calling doctor, HIPPA laws prevent contact.

Back on subject but best for another thread. Bought a 1W NUM03, yes, against advice of others here but $60 is a huge factor. Gonna keep ball lens on and use a epson projector lens as a beam expander. Anything that won't work with this besides maybe burning the lens coating😬? Using one of Rick trents 1st gen heatsinks that were a direct press for 9mm diodes.
 

Gianakakis

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Hmmm. Try an FQP47P06, but you will have to add a small diode across the drain and source junctions. Any small rectifier should do. Connect the cathode to the source and just ground the gate. At 5.5 amps you should dissipate about 789 mW of power in the FET, which is very small considering the amount of power dissipated by any diode. Good luck.
Wait in this video by
Afrotechmods
he does not add a diode so is the video wrong?
Or am i not understanding correctly?
Edit:Ah sorry paul just noticed that I am on the 2nd page anyways so it was the 2nd one I did not understand correctly
 
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