DC motor_N-channel MOSFET's_H-bridge

[speedy]

Hi Thanos ....
Congrats for your new home ...
Congrats every one from UK for that magnificent Olympic opening ceremony .Awesome and it can't be more beautiful
How is that big long Chimneys came out of the stadium earth ?????

BTW ...Thanos :this is really small dimensions you want for high Amps DIY motor controller ...
If you're really talking a bout a "5mmx5mm" even if you're talking about "50mmx50mm" ...
my board is 9.5x10 cm ... for one 50A DC motor ... higher rating is bigger ... but I've got your point .

The HIP4081AIPZ driver chip is a peace of art for technology lovers and a peace of luxury not every one can have it ...

forgive those people like me how can't have a double layer boards or a nearby board etching service .
I'm simply can't buy anything from eBay .It will cost me more than making it like a dinosaur .
There are some people that are beyond last week "Discovery channel ".

[tronicgr]

You are right... I messed up the units... didn't finish my coffee in time

Just for comparison, pololu High Power Motor controller 18v25A dimensions are 4.5cm x 2cm ... I know, its using SMD parts but still, with a little effort you can make a similar specifications motor driver with through hole parts and dimensions around 5cm x 5cm... Maybe sandwich some mosfets vertically...

I have some HIP4081AIPZ driver chips that I bought online some years ago for 10euro each. Now I see that its price dropped to 5euro per piece. Still not a part that you can find easily, I agree on that.

I can't buy anything from ebay either, you are not alone in this. Its a wonderful site if you are a buyer, but treats sellers like shit. I know that from personal experience. And no etching service next door either. Last time I was able to do an order from PCB manufacturer (Futurlec) I had to do a minimum of 25 boards in order to get better price per board.

Anyway...

[motiondave]

single boards is fine here, my soldering is bad enough as it is.

[speedy]

I forgot to say about that this bridge has an isolated data side from the MOSFET driving side .... inside the IR2110 driving IC.
that would make the AMC board completely safe ...

Does any one had any difficulties in assembling it
don't wait and make mistakes ... just ask

AND ... here is some tips for preparing the copper disk I would like to share :
- First , please don't use aluminum instead of copper [ someone asked me for that ] and I'm telling you heat moves fast through copper .
- After finishing the board and the drilling s don't solder any thing yet .
- 8 MOSFET holes in the board should be drilled first ( use 3mm bits ).
- put the disk and the board together against strong light source and center the copper disk to the 8 holes .
- mark these holes onto the disk with a pencil .
- use the same size drilling bit 3mm and complete the 8 holes for the copper disk.
- use a pencil and mark a big circle of 3cm diameter at the center of the disk .
- using a metal saw to make slots into the disk starting from it's edge till the 3cm circle marked edge ... center these slots between the holes drilled before ... [ see picture ]... slots will help directing the heat generated from each mosfet separately to the center of the disk to the attached CPU cooler above it ... keeping other mosfets cooled as it is .

Graphic1.jpg (100.45 KiB) Viewed 3894 times

- then there you go ... continue install every thing else to the board ... when comes to mosfets just bend the legs forward to install there writings faced down to the board and the metal back is up ... and to attach them to the disk [ not the board ] you may wider the board holes to use the screw driver through them from the back side to fasten the bolts .
- use a thermal isolating sheet and some heat compound for each mosfet to ensure a good heat conducting .
- the easy part to attach the fan with the heat sink and centered on top above the disk [ use heat compound ] and attach fan wire to it's socket .

article-new.jpg (25.47 KiB) Viewed 3892 times

that i guess explains my idea for cooling the extra heat generated from mosfet when operating and keeping them within the operating temp .
guys in the computer hardware field would know how much is the cooling power of this CPU fan and it's heat sink .
I wish I have a good camera to give you some photos for all of this .

any questions
best regards ...

[speedy]

Here is some more photos of some regular CPU cooling fans which can be found around almost any where w.w .
more power and working hours needs more cooling capability and stability .

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40008293-M.jpg (15.84 KiB) Viewed 3887 times

- Then we prepare every thing else [IC's ,resistors ,MOSFETS ,... ,etc ]to be mounted onto the board as if it is a SMD device like this .

ic-package-soj-28.jpg (88.88 KiB) Viewed 3886 times

or this .

4524043164_d945884cbb.jpg (65.15 KiB) Viewed 3886 times

or this .

Step3-460x370.jpg (49.79 KiB) Viewed 3886 times

- AND only the through hole jumps when needed between the two boards will cross and will be soldered both sides .
- giving extra space for wider tracks = more amps , and good soldering finish for new users .
- almost no drilling is needed, and just a matter of hocking the two boards with some through hole jumps on the same location for the jump ...

regards

speedy

[tronicgr]

Hi,

Good work. Keep at it.

For comparison you can see how small they can make a similar h-bridge like yours using SMD parts (for single motor though):

High Current DC Motor Driver Module MOSFET control

Thanos

[speedy]

Hi Thanos ...
thanks

BTW ... I can see that you still like eBay .
how about buying one of these and test it for us ? can you do that ? pleeeees .
_____________________________________________________________________
Don't do it ... I'm joking
[edit : OMG ... you actually did it .. ]
I suspect it can handle [90A DC peak = car battery ] ... no way look at the back small mosfets installed ... only four of them ... and current limits for this kind of SMD MOSFET's packaging proves it ... [they cleared the MOSFET's numbers ... but the MOSFET's itself still there ]

T2O85xXXxXXXXXXXXX_!!407779758.jpg (173.02 KiB) Viewed 3875 times

and due to the size of components I'm forced to use , then clearly I can't defeat SMD boards in size ...


And, one more thing ...
to support my theory ... look at how the big capacitor mounted to there board ...

T2zR5xXXRXXXXXXXXX_!!407779758.jpg (154.43 KiB) Viewed 3876 times

BTW ... just a modification I want to make too ...
can your LCD of the AMC controller board be mounted above the ATMEG644 saving space ... like this

esqt_PC1042646a694179446dabdfe3a2b352932c5.png (67.9 KiB) Viewed 3876 times

think about it ... sorry may friend, I still don't have a camera .
best regards

[tronicgr]

Hi,

Yes, as you seen here, I already got that motor driver and tested it. It was a little failure but I think it may been just the specific driver already damaged or material failure during its production. Nothing that can be seen with a simple power-on test that they perform.

Anyway, I'm testing now the other dual motor driver and passed all my tests with flying colors!!! I was just taking a break before I made a video about it. It has 4x BTS7970 chips on it and an 74LS244 for signal conditioning.

The mosfet's can provide the same power either in SMD or TO220 package. The actual transistor silicon die in them is pretty small! They just add more copper around the junction to allow more current or better heat distribution. On that cheap motor driver they scratched the mosfet's numbers so others can't copy their design, its a normal tactic for many circuit manufacturers to try to make it harder for industrial espionage reverse engineering.

Of course you can mount through hole components on surface mount pads, with a little effort.

Why stack the LCD on the AMC? Most people just extend the cable and place the LCD on a front panel or something.

[tronicgr]

Hi,

Just an update...

The BTS7970 chips are also available in TO-220 package, maybe you can try them in a DIY version PCB. In the link below:

http://www.ebay.com/itm/BTS7970-BTS7970P-High-Current-PN-Half-Bridge-Infineon-/110680114984


Thanos

[speedy]

BTS7970 nice one but still low amps than yours ...