Planning DIY TPS63000 based driver

[xStatiCa]

I wonder how long will it run at that amperage in a closed area (like in a host).

 

[Leodahsan]

gratz

 

[jib77]

Awesome! Congrats.

I got my station and parts yesterday ... I think I managed to kill the TI chip Ill try replacing it today.

 

[Rafa]

Awesome! Congrats.

I got my station and parts yesterday ... I think I managed to kill the TI chip Ill try replacing it today.

What have you done wrong?

 

[jib77]

What have you done wrong?

The was my first time using a hot air station, I think I went to high and maybe too long on the reflow profile. Also the only solder paste I was able to get locally is not good for parts this small, the bearings are too big and doesnt stick well to the pads.

 

[Rafa]

I don't know if dave advised you buy you should not pass 3-4ºC/second.
How did you soldered the other boards?

 

[jib77]

How did you soldered the other boards?

I did them by hand with two soldering irons. For the QFN I put a small pillow of solder on the chip's thermal plane and the pin pads on the board. I heated the ground plane on either side of the chip until it reflowed into place. Then I did the blob meathod to reflow the solder on the pads.

 

[erdabyz]

Okay dudes, my driver doesn't work anymore. I've screwed it... but I think it's not beyond repair.

It was getting a bit hotter than it should, I hadn't noticed it because it dissipates heat so fast that it went from untouchable to warm in a matter of seconds, so when I touched it after testing I felt it warm. I did a test touching it while working and it was actually getting untouchable within 10 seconds, and the temperature kept climbing. So I revised the design and I realized a PCB failure, I had ignored the upper and lower thermal paths of the TPS. No big deal, just scratch a bit of soldermask in those areas and apply a bit of solder and.... not working anymore.
I'll try to repair it tomorrow. Maybe some solder flowed under the IC shorting two pads or anything like that.

EDIT: Couldn't resist: it's repaired.

 

[Rafa]

I did them by hand with two soldering irons. For the QFN I put a small pillow of solder on the chip's thermal plane and the pin pads on the board. I heated the ground plane on either side of the chip until it reflowed into place. Then I did the blob meathod to reflow the solder on the pads.

You did it the hardcore way, :crackup:


David dont screw up those boards:yabbmad:

 

[jib77]

Success. Measured 1.14 Amps w/ 4V dummy load! Temp only 49ºC(120ºF) @ about 30 seconds. Hell yeah!

I had to replace the TPS ... luckily I ordered 3. I transplanted everything to a new board and did not use paste. I pillowed the pads with regular 60/40 solder applied flux and gently put the parts on top. I used higher temp but held the air nozzle further away and it re-flowed perfectly. The joints are all so perfect.

 

[gillza]

Success. Measured 1.14 Amps w/ 4V dummy load! Temp only 49ºC(120ºF) @ about 30 seconds. Hell yeah!

I had to replace the TPS ... luckily I ordered 3. I transplanted everything to a new board and did not use paste. I pillowed the pads with regular 60/40 solder applied flux and gently put the parts on top. I used higher temp but held the air nozzle further away and it re-flowed perfectly. The joints are all so perfect.

Congratz!!

heh 200th post

 

[Vaporizer]

Way to go guys!

 

[Leodahsan]

congratz!

well, looking at the inductor I see that is not possible to put an effective heatsink, because the inductor is somehow tall..
will it pump more current? heatsinking? maybe adjustable output (pot)? ^^

hell yeah, gratz again

 

[LarryDFW]

jib77;

Good job on the new board.

I have some quality #18650's if you need some to try.

I live in Farmers Branch.

LarryDFW

 

[jib77]

jib77;

Good job on the new board.

I have some quality #18650's if you need some to try.

I live in Farmers Branch.

LarryDFW

Thanks! I already have a couple of your cells + charger. That's what I used to test last night. :beer:

 

[jib77]

congratz!

well, looking at the inductor I see that is not possible to put an effective heatsink, because the inductor is somehow tall..
will it pump more current? heatsinking? maybe adjustable output (pot)? ^^

hell yeah, gratz again

I would heatsink to the bottom of the board where you can make a lot of contact to the ground plane that is sinking the TPS and the OpAmp. On either side you would need a little pieces of aluminum to shim everything you are sinking so they are at the same level. Then attach to a larger piece like a coin or the inside of a host. I dont have said aluminum to test. Adding a pot where Erdabyz suggested requires a new layout on the bottom plane ... Im not sure its worth it. Im not constantly changing currents on my other drivers ... maybe on a rare oc*****n Im harvesting one to use in another build.