FREE DC-DC CONVERTERS!!!

timmeh87 · Post by **timmeh87** » Sun Nov 20, 2005 4:00 pm

this has probably been asked a billion times before, but what is the EXACT <i>average</i> current draw of an n64 and a psone screen. im trying to calculate an average battery life here. so you could also answer my question by quoting the average life you get out of your "x" mAh pack.

nos_slived · Post by **nos_slived** » Sun Nov 20, 2005 6:01 pm

I can't give you any times, but I can tell you that if you use the screen unmodded, it draws about 750mA, 350mA with the LED mod, and you could probably use a bit less power if you replace the 7805 with a more efficient regulator/ DC-DC convertor. The N64's power draw varies a lot, depending on what game you're playing. You're using a more efficient convertor for your 3.3V line than others, so you will use a bit less power than most people.

timmeh87 · Post by **timmeh87** » Mon Nov 21, 2005 5:38 am

hm. so lets say i use two 12,000mAh batteries, and realistically i get 9,000mAh out of them... and lets say the whole mess will draw 1.25A. so then I'd get... FOURTEEN HOURS of battery life?! wow. thats better than my ds. but i guess its also 3 times as big.

daguuy · Post by **daguuy** » Mon Nov 21, 2005 5:57 am

but where are you gonna get a practical 12,000 mah battery?

Post by **Gamelver** » Mon Nov 21, 2005 6:08 am

the answer is, of course, nowhere

...

timmeh87 · Post by **timmeh87** » Mon Nov 21, 2005 6:58 am

.

We use a 12,000 mAh battery for the solar car. here is part of the datasheet (i was not given permission to post the whole thing...)

http://muss.cis.mcmaster.ca/~bernast/Ba ... 0TABLE.pdf

nos_slived · Post by **nos_slived** » Mon Nov 21, 2005 7:47 am

A solar car with batteries, interesting...

That's pretty good, because 2 together will be about 1lb, and those are great batteries! It will probably draw more than 1.25A, because 0.8A is about a minimum for the 3.3V line, which is usually closer to 1.3A. I can't remember what the 12V line is, but I think it's usually about 0.3A-0.5A. So Even with the screen LED modded, you're looking at about 0.35A + 0.4A + 1A = 1.75A, which can go up some more too. You will still get play time. What are those batteries, li-ions? Do you guys get them specially made, or do you have the name of a distributer?

Post by **marshallh** » Mon Nov 21, 2005 8:48 am

I use a 7 AH lead-acid bettery. Works for me! I get about 4hours out of it.

timmeh87 · Post by **timmeh87** » Mon Nov 21, 2005 9:02 am

wow... lead acid. doent that weigh a ton?

---

all solar cars have batteries, otherwise they would be pretty pathetic... they couldnt drive at night or on cloudy days. The total pack capacity on our car is about 4.5kWh. im snot sure what it is in Ah.

anyhow. the batteries we got are not actaully commercially avaliable, we bought them from a company (electrovaya) that makes laptop batteries - those are the cells that they use inside of them. In all likelyhood they would not sell anything to you unless you ordered a LOT (we ordered about 120. it cost like 12 thousand dollars canadian or something)

and they are li-polys. it says so right on the datasheet

but yeah, if youre looking for some high density lithium batteries, theres another thread here called "best way to power an n64 for long time light weight" with some links to some good ones (6,000 mAh for 25 bucks)

Post by **Gamelver** » Mon Nov 21, 2005 9:06 am

ooooh....nice batteries

....a bit big, yes, but still nice

.....

timmeh87 · Post by **timmeh87** » Mon Nov 21, 2005 9:35 am

well they are big in two dimensions, but pretty flat. i made some 3d models of how i plan to fit it all together, ill post them tomorrow, if not today.

G-force · Post by **G-force** » Mon Nov 21, 2005 3:22 pm

Thanks for the suggestions tim and marshall. I'll check those out. That regulator marshall suggested looks worth a try, since they offer free samples. I've tried regs before and had no success, but others say they work, so I'll give it a shot. The DC-DC from maxim looks a bit difficult, but my dad should be able to help me figure it out. He can do anything, I swear. It's insane how much he knows.

nos_slived · Post by **nos_slived** » Mon Nov 21, 2005 3:57 pm

timmeh87 wrote:all solar cars have batteries, otherwise they would be pretty pathetic...

Joke, hence the ":P"...

timmeh87 wrote:anyhow. the batteries we got are not actaully commercially avaliable, we bought them from a company (electrovaya) that makes laptop batteries - those are the cells that they use inside of them. In all likelyhood they would not sell anything to you unless you ordered a LOT (we ordered about 120. it cost like 12 thousand dollars canadian or something)

I thought it would be something like that.

timmeh87 wrote:and they are li-polys. it says so right on the datasheet

Oops, missed that.

If only we had a super cheap energy source... How much power do you think I could produce by hooking a generator to my bike?

soundwave · Post by **soundwave** » Mon Nov 21, 2005 4:40 pm

*O* works at a petstore, have him hook up generators to the hamster wheels.

timmeh87 · Post by **timmeh87** » Mon Nov 21, 2005 4:41 pm

probably like 400 watts. you chould build a 64 into an exercise bike. then youd have to exercise or else your game will turn off. we can sell it to obese american children.