Joined: 08 Nov 2006
Posts: 1265
Location: Adelaide
i think he has been on holidays and just got back today or yesterday from my emails with him so give him another day or 2.
Wed Jan 02, 2008 9:47 pm
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
Hey guys just wondering what part number the voltage regulators are on the ibc, i'd assume they're two of the same.
Kinda misplaced my smashed off one... _________________ ( •_•)
According to the schematics, the standard regs are a 7812 and a 7805. The Switchmode is a LT1170HVCT. Depends what version of the IBC you have, I believe v2's have a surface mount switchmode reg instead of a 5 leg TO220 one. _________________ https://www.halfdonethings.com/
Mon Mar 31, 2008 8:04 am
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
Ah thought they were different. The switch mode is smd on mine.
Hmm now to work out which went where... _________________ ( •_•)
The schematic is in the docs
The 12v regulator is connected to the switchmodes output then on to the 5v, Both are connected to ground though. _________________ Mechanical engineers build weapons, civil engineers build targets
Mon Mar 31, 2008 8:34 am
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
Was wondering... Is it at all possible to mirror the IBC? That is run just one motor at the current capacity of both H bridges? I suppose a Y cable would make sure both channels are identical, but would linking both wires up cause serious problems? _________________ ( •_•)
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
Theoretically it should work,
its unlikely the two sides will both be driving exactly in sync, with the pwm outputs, but this shouldnt cause a problem. I havent actually tried that though, so I cant guarantee it.. I may have overlooked something.
One possibile disadvantage would be the potential for more complete damage.. - if one side of the bridge overloads and fails in a short-circuit condition (the most common failure mode), the other side will then be attempting to drive a very low resistance short circuit right next to it with no intervening wires or anything, so it will probably rapidly follow the first failure into destruction immediately taking out more fets and possibly tracks in one go. (meaning any bangs will be bigger ones
But it should reduce the likelyhood of any bangs - just remember to take the mixing jumper off so both channels are producing the same output and arent fighting each other ! _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Mon Jun 23, 2008 1:18 am
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
possible hickups you might have.
1: the two sides wont have the same drive outputs, they will be "just a little" different, though they will probably overlap.
2: they wont current share as a result.
Put some inductors on the wires from each sides to the motor, that will help them current share. _________________ Mechanical engineers build weapons, civil engineers build targets
Mon Jun 23, 2008 9:57 am
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
Hmm the threat for total fet damage is a little worrying, its a lot of them!
I understand that they won't be perfect in sync, was just interested considering the sidewinder can apparently do it. Cheers... _________________ ( •_•)
you can do it, just saying adding some inductance to the output will help protect everything _________________ Mechanical engineers build weapons, civil engineers build targets
Mon Jun 23, 2008 11:50 pm
Fish_in_a_Barrel
Joined: 30 Sep 2006
Posts: 673
Location: Perth, Western Australia
I'm planning on hacking my IBC for other things at the moment, any advice on if running the board without the uC inserted (ie, leaving things like the crystal and other components floating) will damage anything else on the board?
Mainly looking at stealing the power side for a few different projects and will only be controlling certain lines.
I guess I would have to tie the outputs from the chip socket that I am not using to ground via resistor. So just wondering about the inputs to the chip socket. _________________ They say that he crossed the fine line, from insanity to genius.
Tue Dec 22, 2009 6:43 pm
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
Jake is the Guru when it comes to lobotomising IBC's and running an external brain.
I recall theres a bit of non-intuitive weirdness driving the HIP chips inputs. Its been a while, something to do with the HIPs input logic allowing the micro to drive it by pwming the low side and using the high side for braking, but its been a while.
If jake cant help you, I'll dig up some notes and remind myself of what I'm talking about _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Tue Dec 22, 2009 7:08 pm
Fish_in_a_Barrel
Joined: 30 Sep 2006
Posts: 673
Location: Perth, Western Australia
I was just refreshing myself on that part, it's all good. They made them relatively idiot-proof (assuming you know exactly what you are doing )
Purely looking to avoid random damage from physical connections. _________________ They say that he crossed the fine line, from insanity to genius.
Tue Dec 22, 2009 7:20 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
I didn't notice any issues leaving the input side of things open.
We just hacked a DIP socket with wires on then urethaned a block onto the back to hold the wires so they didn't fatigue.
You do need to watch that you don't drive the hips at 100% PWM, they need the low pulse to keep the bootstrap charged. _________________ Mechanical engineers build weapons, civil engineers build targets
Tue Dec 22, 2009 10:05 pm
Fish_in_a_Barrel
Joined: 30 Sep 2006
Posts: 673
Location: Perth, Western Australia
That was the plan, although no urethane on hand. I'll just see how it goes for the moment...
I've seen that one, and that it's the high side that switches to make the charge pump. _________________ They say that he crossed the fine line, from insanity to genius.
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