Progress report: SNES portable using the old 1990 SNES

Post by **marshallh** » Sat Nov 12, 2005 8:51 pm

Hm.. I'm confused. From the new pictures you added, it looks like an LM2677. But the min input voltage is 8v, isn't that li-ion battery 7.5 or whatever? I checked with National and it supposedly doesn't come in a 8pin DIP. I'm assuming this is the datasheet..
http://www.national.com/ds/LM/LM2677.pdf
I dont see an inductor in your photo, is it somewhere else or is it some weird package?
I'm really interested in how you pulled this off (I'm looking to do the same thing myself.)

Scary how I was thinking of moving the APU just like you did...

Dubs · Post by **Dubs** » Sat Nov 12, 2005 9:23 pm

b52down wrote:
Dubs wrote:Did you take the audio of the main board or the smaller one?
I got the audio of the main board. I believe pins 11, 12 are the left and right channels.

This might seem like a stupid question, but is the smaller board even needed?

Post by **marshallh** » Sat Nov 12, 2005 9:44 pm

Yes. it's the APU (audio processing unit) that generates the SNES's sound. If you take it out the SNES won't even start up.

b52down · Post by **b52down** » Sun Nov 13, 2005 12:30 pm

marshallh wrote:Hm.. I'm confused. From the new pictures you added, it looks like an LM2677.

It is a LM2672--use http://www.national.com/ds/LM/LM2672.pdf

But the min input voltage is 8v, isn't that li-ion battery 7.5 or whatever?

I tested the unit on my breadboard--it will work at 7.5 V/7.2 V--just keep the wiring as short as possible.

I dont see an inductor in your photo, is it somewhere else or is it some weird package?

The inductor is the greenish looking "resistor" with the goldish colored band. Don't wire the 100 uF cap like in the picture (I was trying to relocate it at the time), it will lower the output voltage greatly.

The parts for my switching regulator, are as follows (allied electronic cat numbers):

Cb = 0.01 uF 50V ceramic capacitor (862-2130)
L1 = 47 uH inductor (895-6006)
Cin = 100 uF 50 V cap (I already had one of these)
D1 = 3.3 A 50V Schottky Rectifier (273-0076)
Cout = 68 uF Capacitor (I already had one of these)

You don't need to hook up SS, SYNC, and on/off.

What is cool about this type of regulator--you could connect a bunch of batteries together--up to 40V and still get 5V! without heat generated.

Scary how I was thinking of moving the APU just like you did...

Rebuilding the traces after I "ripped some of them loose" was a "fun" exercise. I had thought I destroyed the board, and ended up ordering two more consoles through ebay, but I fixed the problem by the time I received them!

Post by **marshallh** » Sun Nov 13, 2005 12:48 pm

Ah, thanks. That answered a lot of my questions. This one supposedly works form 6.5v up. The different part number also expained the DIP-8 package.

b52down · Post by **b52down** » Sun Nov 13, 2005 1:10 pm

marshallh wrote:Ah, thanks. That answered a lot of my questions. This one supposedly works form 6.5v up. The different part number also expained the DIP-8 package.

The inductor partnumber was wrong it should be: (895-6128) I think the other part number was a 0.47 uh inductor, which is wrong.

Cb = 0.01 uF 50V ceramic capacitor (862-2130)
L1 = 47 uH inductor (895-6128)
Cin = 100 uF 50 V cap (I already had one of these)
D1 = 3.3 A 50V Schottky Rectifier (273-0076)
Cout = 68 uF Capacitor (I already had one of these)

SNESguy · Post by **SNESguy** » Sun Nov 13, 2005 1:23 pm

One could also just bypass the sound card issue by using a 1992 or newer SNES. They don't have the sound circuits hanging off of the mainboard.

Don't mean to sound like a smart-ass, but that was what I did in my second SNESp.

b52down · Post by **b52down** » Sun Nov 13, 2005 2:36 pm

SNESguy wrote:One could also just bypass the sound card issue by using a 1992 or newer SNES. They don't have the sound circuits hanging off of the mainboard.

Don't mean to sound like a smart-ass, but that was what I did in my second SNESp.

I bought the console on ebay. Unfortunately, I did not have that info--even if I did, I don't know if the person I bought it from would be able to tell me what kind of motherboard the snes had.

My next unit will use the "mini board"--as I aquired one recently.

warmachine · Post by **warmachine** » Tue Nov 15, 2005 10:17 pm

You play Earthbound, therefore, you rock! Are you in the PKHack forums?

b52down · Post by **b52down** » Fri Nov 18, 2005 5:43 am

warmachine wrote:You play Earthbound, therefore, you rock! Are you in the PKHack forums?

I've been to them, but I haven't posted to them.

I think that Earthbound is the bench mark of RPG. Even with cheezy graphics and music, lack of violence, and political correctness--I am mysteriously drawn towards its wit.

I would write more, but for some strange reason a statue of a pencil is blocking my way.

bioniclebert · Post by **bioniclebert** » Fri Nov 18, 2005 5:47 am

Earthbound=probably best game, EVER. I'm serious. PK hack was fun, I'm not shure whY i stopped...

Ah starmen.net. I watched it as it was just turning into a new phase, when the Eartbound 64 cancellation, the arise of mother 1+2, and the Newest appearance of yup, Mother 3!

Got Mother 1+2 in the DS now actually!

Nintendo .com forums
Go to LEGACY SYSTEMS, and search for "on topic-earthbound." I joined in late, but kept it alive probably for months.