3V line at 800mAh - Is this enough

chodges84 · Post by **chodges84** » Thu May 19, 2005 8:01 am

hmm,

I guess it won't be, but I can't find one higher, other than PSP, but they run at 5.2V or something.

Any one got any ideas? I was thinking of 2 in parallel, would this work, and give me 1600mAh out to the N64?

Of course this would take up mo0re space than one? What about a GBA or GBA SP convertor?

Thanks.

Post by **gannon** » Thu May 19, 2005 8:19 am

well, a battery (I assume you're talking about a battery) that size would power the 3.3V line of the n64 for around 30 minutes.

chodges84 · Post by **chodges84** » Thu May 19, 2005 8:55 am

no, sorry, i meant a DC-DC car convertor.

The only one's I can find will only output 800mAh of current, so this probably isn't going to be enough to power the N64?

but I can't find one higher, other than PSP, but they run at 5.2V or something.

Any one got any ideas? I was thinking of 2 in parallel, would this work, and give me 1600mAh out to the N64?

Of course this would take up mo0re space than one? What about a GBA or GBA SP convertor?

Thanks.

(that makes a bit more sense)

Post by **gannon** » Thu May 19, 2005 8:59 am

2 in parallel would be fine. Only thing I can think of is that 3V on the 3.3V line is getting awefully close to the cut off line. I've had a few n64s that didn't work with that low voltage.
I'd recommend getting a switching regulator though. It's not as effecient as a dc-dc converter, but works well.

chodges84 · Post by **chodges84** » Thu May 19, 2005 1:20 pm

Gannon my man,

I've got a few questions, whilst I have your attention.

I think I have found a switching regulator you were talking about. here:

http://www.eurobatteries.com/sitepages/ ... 20Adaptors

Q1: 12V in, 3.3V out. It is rated at 2100mA, Will it always out put 2100mA, (as this will surely drain the batteries quicker), or does it always output 2100mA? I'm 99.9% sure it is the first option, but I need to be 100% sure that this is the thing i need. Is it?

Now, cast your mind back to July 2004, the 27th to be exact. Can't remember? I'll jog your memory (post 10)

http://benheck.com/ipw-web/bulletin/bb/ ... e&start=15

Q2: You say about the 5V input, I assume you mean into the N64, so If i were to use 1 of these switched regulators above (set at 5V), before inputting into the N64's 7805, I could increase battery power?

Q3: Also, If I were to use a switched regulator at 7V, rather than a 7808 to power the PSOne screen, would that work?

Q4: Refer again to the 27th July last year, and a post later on in the thread. You mention battery power. Would 10 AA's rated at 2100mAh or 2 7.2V 3000mAh Remote Control Car batteries give a longer playing time?

Q5: The switched regulator above mentions only 12V DC input, would the 2 RC batteries at 14.4V (if i were to go that route) be too much for it?

Sorry abotu all that, If you could answer those questions I would be eternally grateful.

Many Thanks.

Post by **gannon** » Thu May 19, 2005 1:33 pm

A1: It can output a max. of 2100mA. It won't take more than it needs.n, 3.3V out.
A2: Yes, using both a 3.3V and 5V switching regulator would be fairly effecient. I'm not sure how much power it'd save you though on the 5V line.
A3: Yes, but you'd need to input ~8 volts into a certain part of the LCD. No big problem there.
A4: RC batteries definitely.
A5: It should be fine. I'd recommend finding a 7.2V input switching regulator though, that way you can still use 2 RC battery packs, but have twice the play time.

chodges84 · Post by **chodges84** » Thu May 19, 2005 1:46 pm

ok thanks,

With regard to a 'Switching regulator' (which i can't seem to find in the UK), does it do the same as a Car Convertor thing, but takes 7.2V rather than 12v?

I Could then wire up 2 RC batteries in parallel? Straight from the battery into the N64 5V and PSone screen, and then, battery to 'switching regulator' to 3.3v line on N64?

Sounds good, if thats right.

Warrior_Rocker · Post by **Warrior_Rocker** » Thu May 19, 2005 6:31 pm

thats been the issue of many debates, personally i dont think most car adaptors will take 7.2 down to 3, but its possible, try it, if it dosnet its only a 6 dollar mistake..., if anyone else has anything else to say on that?

chodges84 · Post by **chodges84** » Fri May 20, 2005 6:38 am

warrior_rocket,

I don't think they will either, but these switching regulator things gannon's talking about sound promising.

I've managed to locate some UK based ones, if someone could tell me if they are good, I'll be laughing.

here they are: http://uk.farnell.com/jsp/endecaSearch/ ... cSelection

woah, thats a long URL. I was thinking of the bottom one in the list, but its got 16 pins? SOme of them have got 5, would these be ok? The top one on the list looks good as well.

Thanks again.

Warrior_Rocker · Post by **Warrior_Rocker** » Fri May 20, 2005 1:47 pm

umm, problem is those might require additional circuitry to be created, and that is not far outa my league, but i just dont know what kinda circuit they would need specifically

nos_slived · Post by **nos_slived** » Fri May 20, 2005 9:59 pm

chodges84 wrote:I Could then wire up 2 RC batteries in parallel?

I think you meant series. If you want 14.4V, you better mean series. I wouldn't suggest hooking them up in parallel anyways, because they are rechargeables.

chodges84 · Post by **chodges84** » Sat May 21, 2005 6:34 am

yeah i meant series to give me 14.4V. Bit of a bugger though with a switching regulator if I need extra circuitry. What about 14.4V into this beast;

http://www.eurobatteries.com/sitepages/ ... 20Adaptors

Would that work, or would I need to knock it down to 12V (with a 7812) first?

I'm really going for 3.3 because I've heard some people saying about distorted video and sound if you only supply it with 3.

*o* · Post by ***o*** » Sat May 21, 2005 3:27 pm

that would work

i dont think having a few more volts would be an issue because regulators have a very wide range it just if the resistors can take the extra load

Warrior_Rocker · Post by **Warrior_Rocker** » Sun May 22, 2005 11:11 am

yea, your probably right, just remeber most for instance 1.2v Li-Ion
cells can easily when charged run 1.5v so w/ those 7.2v batts you could easily get 9v outa each of those rc batterreies, then for 18v thats pushing it, however you can certianly try, and as most of those car adaptors use a varialbe voltage regulator, you can probably over power them to a point, just make sure you voltmeter its output before you go attaching it to your n64

chodges84 · Post by **chodges84** » Sun May 22, 2005 12:18 pm

will do,

I'll have to dig it out from somewhere. I may even just go back to the 10 AA idea for now, so that'll be 15V tops when fully charged.

I actually managed to get my N64 apart today after I finally got hold of a Gamebit screwdiver.

I'll get a lot more done tomorrow, and hoping to have a playable portable in some form by the end of the week.

The I'll get craking on a proper case and probably moving the cart slot. Can't wait.