Gamecube mA measurements for individual voltage lines.

Electric Rain · Post by **Electric Rain** » Wed Mar 28, 2007 1:53 am

Alright guys, I've got them. I measured the mA draw for each individual voltage in the Gamecube. For testing, I used SSBM, Soul Caliber II and Super Mario Sunshine. The difference between games was small... too small to keep separate records of. The following measurements are the lowest to highest ratings I saw at any given moment during measuring. This means that it never dipped below or went above the ratings I gave. Here they are:

Code: Select all

1.9V = 1800mA - 2300mA
3.3V =  700mA -  900mA
5.0V =  300mA -  400mA
 12V =    4mA -    5mA

The 1.9V line never went above 2100mA during gameplay, but raises to 2300mA during power up.

<Edit by vskid It has been found that the 1.9V line actually draws 6000-6600mA.>

During testing, I found out that the 5V line is only used for the DVD spinner motor. It quickly dips to zero a few times when the laser is reading, and it is the only thing that is affected when the 5V line is disconnected. The 5V can be cut off as long as it's not trying to load from the disk.

I also confirmed that yes, the only thing the 12V line is used for is the audio. I accidentally shorted the 12V line to ground for about 15 seconds without knowing it, and it killed the audio (and only the audio). I'm pretty sure it just blew a fuse on the PSU, because I was able to feed the 12V line straight from the power switch/fan board after that and the audio was fine. The 12V line was measured without the fan being part of the circuit, for three reasons. One, the fan is feed directly from the power input, having nothing to do with the PSU (which is what I was measuring), two, the current draw is listed on the fan anyway, (It was 50mA, if it's that important.

) and three, I personally will probably be replacing it with a 5V fan on my GC laptop. Or maybe not, we'll see. The important thing is that the BOARD only takes 4-5mA. This means that only a very very small step-up regulator is needed to supply the 12V line.

I think that's all I've got for now, I hope this information is useful to you all. I've got to go clean up now, then I'm off to start designing my new power supply.

Post by **CronoTriggerfan** » Wed Mar 28, 2007 7:44 am

Wow, nice collection! This'll be great for portablizing! Sticky, mayhaps?

CTFan

Post by **CronoTriggerfan** » Wed Mar 28, 2007 7:45 am

Wow, nice collection! This'll be great for portablizing! Sticky, mayhaps?

CTFan

TheOnlyOneHeFears · Post by **TheOnlyOneHeFears** » Wed Mar 28, 2007 1:01 pm

Brilliant collection of info! I second the sticky motion

Any more news on your PSU?

Electric Rain · Post by **Electric Rain** » Wed Mar 28, 2007 5:45 pm

I'm glad you guys find it useful.

It would be cool to have this thread in the sticky, it would be my second thread to get stickied!

(The other one is my N64 Gamecube joystick mod.)

I'm coming to a sad realization, however. Why am I designing a new PSU? I originally was going to do it so that the Gamecube could run off of a lower voltage. I knew the 12V line couldn't have been under that much draw, and it turned out I was right. 5mA? That's pathetic. Do you guys think it would be a waste of my time to design a completely new PSU for it? Why wouldn't people, now knowing that the 12V line only needs 5mA, just mod the existing PSU with a small 12V step-up regulator? Doesn't that seem easier/cheaper all the way around?

I was looking forward to selling these, too. >.>

I'll probably still design one for my GC laptop, just so I can have my screen's power supply, the cube's power supply and the protection/charging/level monitoring circuits for my Li-Ions all on one MAIN PSU board... but would anyone else actually end up buying one of these?

Post by **Triton** » Wed Mar 28, 2007 8:15 pm

woah, it just hit me that the cube basically runs on 5v, thats nuts! too bad it draws like 3a lol

Metroid fan · Post by **Metroid fan** » Wed Mar 28, 2007 8:36 pm

So on the twelve volt line we could just add a step up regulator (YES!) This could really get me continuing on my GCp if I could get a step up! Where's a good one that I could get free online?

Electric Rain · Post by **Electric Rain** » Wed Mar 28, 2007 8:42 pm

You guys, always about the FREE.

I'm sure TI probably has a 12V step-up, but be careful, they're gonna catch on to our community soon.

Metroid fan · Post by **Metroid fan** » Wed Mar 28, 2007 8:52 pm

Why spend money on stuff

TI will get us one of these days...

Electric Rain · Post by **Electric Rain** » Thu Mar 29, 2007 7:17 pm

Found one (a good 12V step-up). The TPS6734I from TI should be perfect. It can be powered off the 5V line. I think you can get samples of it, but it's a little more complicated than the 3.3V reg from them that N64 portablizers are used to. It requires 5 external components, so look at the "Typical Operating Circuit" on the datasheet to find out what other parts you'll need. It's probably the simplest step-up you'll find anyway... so...

Website · Post by **Life of Brian** » Thu Mar 29, 2007 9:20 pm

Electric Rain wrote:Found one (a good 12V step-up). The TPS6734I from TI should be perfect. It can be powered off the 5V line. I think you can get samples of it, but it's a little more complicated than the 3.3V reg from them that N64 portablizers are used to. It requires 5 external components, so look at the "Typical Operating Circuit" on the datasheet to find out what other parts you'll need. It's probably the simplest step-up you'll find anyway... so...

So write a "how-to" and you'll get put in the sticky even more! Huzzah! Seriously though, props to you!

timmeh87 · Post by **timmeh87** » Sat Mar 31, 2007 10:46 am

before you get all excited, maybe read the datasheet

the minimum rated current in that converter is 120mA (page 6 of datasheet)

from the datasheet:

pulse-skipping mode
At very light load currents, the TPS6734 cannot generate drive pulses sufficiently narrow to maintain regulation
and operate at 170 kHz. Under these circumstances, the converter operates in a pulse-skipping mode, in which
cycles are skipped. In pulse-skipping mode, the waveforms are irregular and the output ripple contains a
low-frequency component that may exceed 50 mV peak-to-peak.

and also, the graph shows that the efficiency drops to about 78% at 10mA (page 13)

It might work but I'm almost sure someone could find a better one. I dont have time to go searching for you right now though.

Electric Rain · Post by **Electric Rain** » Sun Apr 01, 2007 3:17 am

timmeh87 wrote:before you get all excited, maybe read the datasheet

the minimum rated current in that converter is 120mA (page 6 of datasheet)

from the datasheet:
pulse-skipping mode
At very light load currents, the TPS6734 cannot generate drive pulses sufficiently narrow to maintain regulation
and operate at 170 kHz. Under these circumstances, the converter operates in a pulse-skipping mode, in which
cycles are skipped. In pulse-skipping mode, the waveforms are irregular and the output ripple contains a
low-frequency component that may exceed 50 mV peak-to-peak.
and also, the graph shows that the efficiency drops to about 78% at 10mA (page 13)

It might work but I'm almost sure someone could find a better one. I dont have time to go searching for you right now though.

Huh... didn't see that part. Nice catch.

Post by **Triton** » Mon Apr 23, 2007 3:04 pm

bump for NEEDS STICKY! srsly u guyz

Electric Rain · Post by **Electric Rain** » Mon Apr 23, 2007 5:45 pm

Why thank you, Triton! I'm glad you feel it's worthy.

Edit: *two days later* Guess nobody gives a crap then?

The GC info thread hasn't been updated since 2005! So... what, is everyone too scared to make a GC portable or something? Are you all just gonna stick to your generic, boring little NESOAC portables that all blend together? I don't understand why this generation of consoles is so unpopular among portablizers. They're not that THAT MUCH harder, and don't even say they cost too much. I got a broken GC off of eBay for $20.50 SHIPPED and fixed it within 5 minutes of opening it. >.>

Tell me... is this information just... not actually all that useful to those making GC portables? Or is it just that NOBODY'S MAKING A GC PORTABLE?!