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FrozenGate by Avery

[UPDATE] V4 BlitzBuck, Available Soon!

Re: BlitzBuck V3, Available Soon!

No, but CajunLasers does. See the link in my sig.
 





Re: BlitzBuck V3, Available Soon!

Well then I guess I will have to hurry up with that paypal account :toilet:
so I can place all my orders!
 
Re: BlitzBuck V3, Available Soon!

Well, I just hooked up my blitz buck to my test load and it's running at 2A and getting VERY hot in about 30 seconds. Are you sure these don't need heatsinking?

The driver also doesn't seem to be very stable. It starts at 1.9A and goes up to 2.05A as it heats up.
 
Re: BlitzBuck V3, Available Soon!

These are perfectly stable on my test load... it seems like your problem may be the testload itself heating up. Resistors change their resistance, and thus the ohmic voltage drop (the way we measure current) as they heat up, and at high currents like 1.9A, it will definitely do that.

As far as heating up the driver... yes, I am sure. I have tested numerous of these up to 2.2A without heatsinking for a minute or so. While they will get warm, they stay stable.... Mind sending me some pictures? Again, if you aren't satisfied or think you got a broken one, you can always send it back to Clif and he will send you another one - I sent him about 10% extra boards for that exact reason.
 
Re: BlitzBuck V3, Available Soon!

I'll test the other one I have today to see if it's my test load. Which would be the accurate measurement then? The readout at the beginning?

This is my set-up:
http://i.imgur.com/DJxqj.jpg

Not using my power supply because it's a POS.
 
Re: BlitzBuck V3, Available Soon!

The first one should be the accurate one. However, to be on the safe side, I would measure current directly using your DMM instead of using the V=IR relationship for your supposedly 1 Ohm resistor.

Your setup looks alright... on my test loads, the positive wire usually leads to the resistor and the negative wire coming from the diodes... are you sure you have your test-load set up properly? Because if it is reverse-polarity'd... that would explain why it's heating up a lot =p

Also: efficiency drops as your output AND input voltage lower. So if you are using 6V to power 3V... it's clearly not going to be able to run unheatsinked at 2A. However, these were designed to use 8.4V to 4.5-5V out.

Do you have the equipment to measure the current draw and voltage of your power supply WHILE you are running it as well as the voltage that the test loading is seeing and the current it is seeing?

Then we can calculate efficiency and see why it's acting strangely.
 
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Re: BlitzBuck V3, Available Soon!

The test load is wired together right, that I am sure of.

I have 3 DMM's so I had to hook it up twice to get all these numbers.

Power supply voltage: 8.35V
Current draw: 1.3A

Voltage at test load: 4.5V
Current at test load: 1.91V
Voltage across resistor initially: 1.91V
The same thing is happening when I measure current from the driver to the test load, it's slowing increasing over time.
 
Re: BlitzBuck V3, Available Soon!

Hmm. That's very bizarre that it is increasing in current, even when not using a test load to measure the current.... That's is very bizarre indeed. Never seen that before in all of the testing I have done of these.... Mind snapping a macro for me?
 
Re: BlitzBuck V3, Available Soon!

Hmmm. That looks fine. Does it slowly increase in current at lower currents, or just at 1.9A?
 
Re: BlitzBuck V3, Available Soon!

Yup, it's acting the same way at both higher and lower currents.
 
Re: BlitzBuck V3, Available Soon!

Hmm. That sounds... odd. It may be the result of overheating, which may indicate that the IC itself is faulty, because everything looks like a clean joint. Is it possible that you can see if the two are related? I.e. does something in particular heat up and then the current rises, or what?
 
Re: BlitzBuck V3, Available Soon!

Would the two "jumper resistors" on that board in ARGLaser's photo make a difference since it looks like both ends of the two are jumpered? I think this may have come up before and I think you said it would matter, just noticed it in the photo however.
 
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