Resistors

[Carmany]

Following the main wiring diagram, it asks for a 2k Ohm Resistor. Radioshack sells a 2.2k, what is the difference between 2.2k and 2k and does it matter?

[thewise1]

That's scientific notation, 2.2k means 2200 ohms, so it's 200 ohms more than a 2k resistor. (2000 ohms)

p=pico=.000000000001
n=nano=.000000001
µ=micro=.000001
m=milli=.001
k=thousand=1000
M=mega=1000000
G=giga=1000000000
T=tera=1000000000000
exa==10000000000000000

That's as far as I know, you can look up more notations on wikipedia, but that's all you need.
2.2k will work fine.

[Carmany]

Alright so even though the diagram asks for 2k the 2.2k will work just fine? Will there be any noticeable difference in the final product?

[Erlex]

I would imagine that since that circuit uses those values to determine the output, yes a 200ohm difference would effect the output enough to be undesirable.

[thewise1]

From what I remember a 2.2 gives out around 3.1v, which is touchy for earlier revisions, I've seen people use 2.2 and it worked, the best one though is 1.8K, it will get you pretty close to 3.3v, but they're hard to find.

[Erlex]

http://search.digikey.com/scripts/DkSea ... 1.8KEBK-ND" onclick="window.open(this.href);return false;
Well after looking all day, I found one.

[hailrazer]

And just to complicate things more. Every Ti board will be different. I used a 2.2k resistor on all 3 boards I have and the resulting output voltage was different on all three.
One was as high as 4.0v and one was as low as 2.8v
So it's best to buy a multipack of resistors and always check with a meter after connecting it to your source but before connecting it to the N64. Because most likely you will need to use a slightly different value resistor.

I am going to go out on a limb and say that is why there are so many people borking their N64p's.

[daftmike]

Ideally you'd use a high precision resistor *like this* to give exactly 3.3V.

[hailrazer]

Ideally you'd use a high precision resistor *like this* to give exactly 3.3V.

Unfortunately it's not the resistors thats the problem, it's the Ti chip. Apparently they have a high tolerance and are not all specced the same.

The results above were with the same resistor and 3 different Ti chips.

[timmeh87]

Theres no way it would give you 4.0v. That's either a 50% error in resistance, or a 21% error in output voltage. Your resistors are specced at 10% max, and the regulator itself, right there in the datasheet, is specced at max 3% output variation.

If you got 4 volts, consider these possibilities in order of likelyhood (my opinion)

- the batteries in the multimeter were dead
- it wasn't a 2k resistor or it wasn't hooked up right
- the regulator was totally fux0red

[hailrazer]

Theres no way it would give you 4.0v. That's either a 50% error in resistance, or a 21% error in output voltage. Your resistors are specced at 10% max, and the regulator itself, right there in the datasheet, is specced at max 3% output variation.

If you got 4 volts, consider these possibilities in order of likelyhood (my opinion)

- the batteries in the multimeter were dead
- it wasn't a 2k resistor or it wasn't hooked up right
- the regulator was totally fux0red

Well think what you might but I have used over 10 Ti regulators and have had to use different value resistors with EVERY one of them to get the desired 3.2v-3.3v. And some had to be (IIRC) as high as 2.8k and as low as 1.3k.

Like I said this probably explains why so many people are ruining so many N64's. And have you noticed the abundance of threads where people aren't getting the proper voltages out of them? I know I have

I suggest that anyone using one try it with a 2k resistor but make sure to check the output voltage before hooking it up to the N64 !!!!

And I ALWAYS check the resistor values with a meter, my meter ALWAYS has good batteries in it, and I ALWAYS got the Ti regulators to work at 3.2v-3.3v once I found the proper resistor value for that Ti regulator

[timmeh87]

Well the three I worked with in the past operated absolutely fine to the best of my recollection. Im kind of tempted to hook up whatever ones I have as an experiment. I still dont really believe you that you are getting regulators that are basically completely broken according to you. These parts are designed to go into machines made by other machines, there isnt a dude at a factory determining the "right" resistance value for each device coming off an assembly line. If TI were to sell regulators that operate as you describe, entire shipments would be returned by angry customers. These things aren't cheap.

Perhaps they are getting damaged due to static (there IS a warning right on the bag that no one takes seriously) or heat, or anything else, they are pretty sensitive parts.

Most of the problems I see seem to be related to conflicting advice on whether to use 1.8 or 2.2k, or 3.1v versus 3.3v. I haven't seen any threads with anyone saying that the voltage they got was wrong.

Just out of curiosity... what did you need ten regulators for?

[hailrazer]

I don't really care if you believe me or not.

And I know how factories work and how these regulators are made.

I needed ten of them because unlike others here I actually build portables.

[ToastBucket]

I needed ten of them because unlike others here I actually build portables.

We're trying our best, hail

[hailrazer]

I needed ten of them because unlike others here I actually build portables.

We're trying our best, hail

I wasn't putting anyone down. Sorry if it came across that way. It was just a smart a$$ way of saying I had 10 because I needed 10 for portables. Sorry.

And what happened was once I found the irregularities on the Ti regulator I started testing the other ones to see if they were different. Thats when I found out that they all registered different voltages with the same resistor.