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Dougboy
2006.08.09, 06:49 PM
I just tried a hybrid fet stack with 2 different kind of fets on each stack. But to kick it up another notch, i aslo have different numbers of fets on each stack. :rolleyes:

With a little expert advice from LBRC, i now run a 2x2 +1. Its basicly two 4562's on the pos side and three 3004's on the other stack. Why do this you ask? Because i have unlimited access to 3004's but 4562's are either hard to find or very expensive. A low budget racer would cut corners and try to work with what i have :(

Supposedly, the forward is now suppose to use the P channel from the 4562's and the N channel from the 3004 to achive optimal performance with only two 4562. Then again, i dont really know the technicalities involved :confused:

After some testing, it does seem to be a little bit punchier. This is my 2nd attempt at a fetjob and its my second successful attempt. I think im starting to get the hang of it

here's a pic. one of the legs look detached in the pic but i can assure you that its only the angle. i checked and rechecked and even checked with a magnifying glass to ensure proper connections

http://img157.imageshack.us/img157/2663/dsc02096fi8.jpg


And since doing a slanted stack was too complex for a soldering novice like me, i had to cut a little bit of the opening to fit the pcb under the cover

http://img90.imageshack.us/img90/1139/dsc02098yo0.jpg

builthatch
2006.08.09, 08:15 PM
I just tried a hybrid fet stack with 2 different kind of fets on each stack. But to kick it up another notch, i aslo have different numbers of fets on each stack. :rolleyes:

With a little expert advice from LBRC, i now run a 2x2 +1. Its basicly two 4562's on the pos side and three 3004's on the other stack. Why do this you ask? Because i have unlimited access to 3004's but 4562's are either hard to find or very expensive. A low budget racer would cut corners and try to work with what i have :(

Supposedly, the forward is now suppose to use the P channel from the 4562's and the N channel from the 3004 to achive optimal performance with only two 4562. Then again, i dont really know the technicalities involved :confused:

After some testing, it does seem to be a little bit punchier. This is my 2nd attempt at a fetjob and its my second successful attempt. I think im starting to get the hang of it

here's a pic. one of the legs look detached in the pic but i can assure you that its only the angle. i checked and rechecked and even checked with a magnifying glass to ensure proper connections

http://img157.imageshack.us/img157/2663/dsc02096fi8.jpg


And since doing a slanted stack was too complex for a soldering novice like me, i had to cut a little bit of the opening to fit the pcb under the cover

http://img90.imageshack.us/img90/1139/dsc02098yo0.jpg

weird! but glad it turned out. you'll notice for the cutout on the chassis, you only need to remove a small amount of material...you can scrape an xacto along the side you want to open up a bit to take material away and have it end up straight/level.

forget about the oblique stack BS.

LBRC
2006.08.10, 12:54 AM
Specs
If everything worked out right when going forward the stack should be able to handle the same 12.4 amps continuous current as a 2x2 4562 stack, this limit is set by the dual 4562 P-channel, with a slightly higher P+N on state resistance, <0.053 ohms verses <0.029 ohms for a straight 2x2 4562 set.

Most of the sacrifice is made in reverse which will only take 10.5 amps continuous current with a P+N on state resistance of <0.126 ohms. Only a problem if you like to run your races in reverse.

The input side of the equation might be interesting; you are driving 3 chips instead of two on the N channel but the 3004ís regardless of their many faults have a notably low gate drive voltage and drive current requirement, in other words it donít take as much to turn them all the way on, which could in real world applications make up for the extra FET and slightly more resistance.

rharris
2006.08.28, 02:29 AM
Because i have unlimited access to 3004's but 4562's are either hard to find or very expensive.

We need 3004 for stock racing. But they are getting hard to find. Where are you buying them from?

Also, I found 4562's from a German supplier on ebay for around $2 each shipped.

Thanks

Dougboy
2006.08.29, 06:18 PM
We need 3004 for stock racing. But they are getting hard to find. Where are you buying them from?

Also, I found 4562's from a German supplier on ebay for around $2 each shipped.

Thanks

I get them from stock cars, my stock cars and other people's stock cars when they get a fet job. Can you please give me the name of the seller because im interested in buying 4562's for $2.

OH btw, any PCB experts out there know if i can safely run a PN anima with this setup?

thanks

rharris
2006.08.29, 07:11 PM
RC-Tech is the seller name.

They had a few more left.

rharris
2006.08.29, 07:17 PM
OH btw, any PCB experts out there know if i can safely run a PN anima with this setup?

I'm no PCB expert, but I run the anima with 2 on the neg and 3 on the positive. No trouble frying the fet so far, but the board glitches from time to time and the throttle gets stuck wide open.

rharris
2006.08.29, 07:27 PM
I was reading in another thread that a 2x2 with 4562's should be plenty to run the anima.

The spec's say that the 4562 can handle 6.2 amps on the P channel vrs the 3004's 2 amps.

When I get my fets in (holding breath) I'm going to soder on 2x1 4562's and run the Anima in my pan car. I'm very hopefull that a single stack can handle it.

rharris
2006.08.31, 04:19 PM
I get them from stock cars, my stock cars and other people's stock cars when they get a fet job. Can you please give me the name of the seller because im interested in buying 4562's for $2.

OH btw, any PCB experts out there know if i can safely run a PN anima with this setup?

thanks

I just checked, and the store here sells them for $2.49. I wish I would have checked first, I'm sure I would have gotten them alot faster then from Germany.

http://shop.tinyrc.com/product.php?productid=16723&cat=0&page=1

briankstan
2006.09.06, 02:41 PM
I was reading in another thread that a 2x2 with 4562's should be plenty to run the anima.

The spec's say that the 4562 can handle 6.2 amps on the P channel vrs the 3004's 2 amps.

When I get my fets in (holding breath) I'm going to soder on 2x1 4562's and run the Anima in my pan car. I'm very hopefull that a single stack can handle it.

Rod, any update on this? I have been really impressed with the 2x1 replacement I installed on my MZM, I picked up an Atomic Stock motor and I'm happy with it, but I would like to know if running the Anima is possible with a single stack.

rharris
2006.09.06, 02:52 PM
Hi Brian,

I'm still waiting to get them in. They have to ship from Germany, so I'm guessing it will take another week.

In other news... I meet up with a guy (Greg) who designs and builds circuit boards for high end projectors. He's got a son that's 12 and is an old R/C buff. The two of them are considering joining the club.

Greg seemed to know all about this stuff. He's supposed to come by this weekend and show me how to test and replace them the rite way.

My 3x2 board is very glitchy at my house, but runs fine at John's track. Greg (my new electronics hero) said he'd bring some equipment by and help me try to figure it out.

I'll keep you posted.

rharris
2006.10.12, 02:16 PM
Rod, any update on this? I have been really impressed with the 2x1 replacement I installed on my MZM, I picked up an Atomic Stock motor and I'm happy with it, but I would like to know if running the Anima is possible with a single stack.

Ok I finally got around to doing this. And yes it's posible.

I set the car up with 1x1 4562 fets. I've been running the Anima for a week now with no trouble. I even did a test where I slammed the car into the wall and held the throttle for 5 seconds to see if I could fry them.

This car was giving me allot of trouble with glitching. The car would take off full throttle from time to time. As it turns out it had nothing to do with the fets. It was a reciever range issue. I extended the antenna using ByeBye's technique and the glitch went away. I can now control the car from over 50 yards away (but you can't see it :D )

I'm going to run a 1x1 4562 setup in all my open class cars now (pan car, and open stock). It's very easy to do compared to a stack. (also a bit cheaper) I may try a 2x2 to see if I can pull it off, but not till I burn out my current set of fets.

briankstan
2006.10.12, 02:24 PM
Thanks for the update. That is perfect. I'll need to get me a anima motor now. :D

rharris
2006.10.12, 03:13 PM
Ok, this is off topic...

In my pan car, I dont' run the anima. I run a PN NM with a 10 tooth pinion, and a single stack. I put a 4562 on the positive side and left the 3004 on the negative side. I did this because I'd fried my positive 3004 and was to lazy to replace both. But I've been running this way for weeks with no problems.

The top end on this car can keep up with just about anything. IE, no one has passed me in the strait. The NM motor has enough torque to drive the 10p off the corner. A smaller tooth and the rear tires get chewed up pretty fast and the car tends to spin out a bit.

To tune for a specific track, I just dial down the EPA for the throttle. I range from 70% to 120%.

I run the 1x1 4562 and the anima in my open class NSX. I run +2 offsets in the front and +3 in the rear. I run a 8 tooth because the anima does not seem to have as much torque as the NM.

But I prefer the pan car setup.