My way of getting 3.3 volts

[scorpio93]

This is how I am currently getting 3.3 volts for my N64. I doubt you'll need a capacitor cause everything should be really close together in a hand held... but you will DEFINITELY need a heat sink. I chose this way over some of the more popular ways to get 3.3 volts cause i was having trouble getting that TI board. I also bought these in bulk for overall 5$ and got enough to make 10 of them

hopes this helps anyone having this specific problem i had, TRYING TO GET THAT DANG 3.3v!!!

 

[eurddrue]

That regulator is linear and will be less efficient then a TI regulator that you can get for FREE. If you need help getting one just say so.

 

[scorpio93]

That regulator is linear and will be less efficient then a TI regulator that you can get for FREE. If you need help getting one just say so.

Less Efficient as in how? It supplies a 3.3 voltage. Also i forgot to say this regulators current is 1.5 amps so it can play jumper and expansion.

 

[Joeyjoe9876]

like drue said the TI regulator is more efficient. just because it supplies 3.3v doesn't mean it is just as efficient. when it comes down to size this regulator needs a heatsink whereas the TI regulator generates less heat and has no need for the heatsink.

 

[ShockSlayer]

Linear regs burn off the extra power into heat.
Ti's DC-DC reuse the power and produce less heat, and at a higher amperage, 2.2 amps IIRC.

DC-DC > Linear regs

SS

 

[jleemero]

While what Drue and SS said is true, it's hardly relevant.

The difference in power consumption will be negligible.

ie "The batteries last 4.5 hours with the TI reg, but only 4.3 hours with the Linear Reg!"

 

[ShockSlayer]

It makes more of a difference if you have a weaker battery, but that's just in general. Also producing mroe heat = bad for a portable.

The key factor for me with the TI is the 2.2A instead of just 1.5A

I've seen the 3.3v line occasionally spike to 1.7A, so using a TI converter I'm safer than with a linear reg.

 

[eurddrue]

While what Drue and SS said is true, it's hardly relevant.

The difference in power consumption will be negligible.

ie "The batteries last 4.5 hours with the TI reg, but only 4.3 hours with the Linear Reg!"

That's two tenths of an hour's time to play Super Smash Bros.

And do DC-DC regs reuse power? I thought I heard they worked differently than that.

 

[Mako321]

I'm pretty sure that it's not how a switching regulator works.

 

[hailrazer]

A linear regulator is basically a variable resistor , as the load voltage changes the resistance changes providing a constant output, hence the heat and inefficiency.

A switching regulator is basically a switch that goes on/off at a fixed rate usually around 50-100khz. The time that the switch remains closed during each switch cycle is varied to maintain a constant output voltage. So there is not much wasted electricity and a lot less heat.

 

[daftmike]

Hailrazer explains it pretty nicely, this page has some more info.

The difference in power consumption will be negligible.

ie "The batteries last 4.5 hours with the TI reg, but only 4.3 hours with the Linear Reg!"

Actually the difference in power consumption will be very significant.

If you use a 7.4V 6000mAh battery, LED-mod PSone Screen(~400mA), the 3.3V line ~1.2A and ~100mA on the '12V' line, theoretically you would get:

LM317 ~ 6/(0.4+1.2+0.1) = 3.53 hours
PTH08080 ~ 6/(0.4+[(1/0.93)(1.2*3.3)/7.4]+0.1) = 5.58 hours

In reality you wouldn't get exactly the battery life calculated, but the difference between a LM317 and PTH08080 for the 3.3V line would be similar. It's because the PTH08080 is 93% efficient at that voltage and current, while the LM317 struggles to hit 45%.

 

[ShockSlayer]

I knew I had it mixed up. Yeah, thanks hail!

Also once more daftmike proves he is superior to all of us.

SS

 

[Mako321]

or he knows how to superiorly use Google.

 

[scorpio93]

Hailrazer explains it pretty nicely, this page has some more info.

The difference in power consumption will be negligible.

ie "The batteries last 4.5 hours with the TI reg, but only 4.3 hours with the Linear Reg!"

Actually the difference in power consumption will be very significant.

If you use a 7.4V 6000mAh battery, LED-mod PSone Screen(~400mA), the 3.3V line ~1.2A and ~100mA on the '12V' line, theoretically you would get:

LM317 ~ 6/(0.4+1.2+0.1) = 3.53 hours
PTH08080 ~ 6/(0.4+[(1/0.93)(1.2*3.3)/7.4]+0.1) = 5.58 hours

In reality you wouldn't get exactly the battery life calculated, but the difference between a LM317 and PTH08080 for the 3.3V line would be similar. It's because the PTH08080 is 93% efficient at that voltage and current, while the LM317 struggles to hit 45%.

You gotta be a robot.

 

[zeturi]

Nah, just make sure to pay attention in 8th grade math class. And know your power draw well. Ah, what the heck, you're a genius, Daftmike.

 

[βeta]

You're not a genius, but it's Dang good that you know what you're talking about.

 

[Basement_Modder]

While what Drue and SS said is true, it's hardly relevant.

The difference in power consumption will be negligible.

ie "The batteries last 4.5 hours with the TI reg, but only 4.3 hours with the Linear Reg!"

That's two tenths of an hour's time to play Super Smash Bros.

And do DC-DC regs reuse power? I thought I heard they worked differently than that.

They do. Its like a Rapid Fire controller, meaning it goes off and on really fast. The capacitor pulses, and the resistor tells the IC what voltage to output. Then it rapidly turns on and off, shutting off the second the voltage reaches a tiny bit above the desired voltage, EG 3.45v, then turning back on when it goes just below the desired voltage, EG 3.15v. It does this so fast that the voltage balances out right in the middle, at 3.3v.

Edit-Woah, there's a second page!

I read up to eurddrue's post and quoted. Boy, I look stupid.

Edit #2- This regulator would be easier to use for the 3.3v line. Heck, you could make an entire GC reg board with these, granted, you'd need a few in parallel for the 1.9v line's amp draw...

 

[eurddrue]

I noticed that Jleemero went oddly quiet... I also noticed that he was quite wrong.

Suck my Kool-Aid packet.

 

[XCVG]

Putting regulators in parallel is a really bad idea IIRC, because you'll never get the voltage quite the same.

 

[Basement_Modder]

Putting regulators in parallel is a really bad idea IIRC, because you'll never get the voltage quite the same.

You can find the resistance the pot is at to get the desired voltage, then desolder it and replace it with a resistor on all the regs.