Battery help

[βeta]

IT'S METAL.

 

[Mako321]

Yes.

 

[superthorn96]

when ever i solder the solder dress up really quickly

so.... is that normal... or do i need a different solderin iron
or different solder

 

[βeta]

It's supposed to cool quickly. Just keep it heated until you've got the joint you want, then take the iron away.

 

[superthorn96]

what's the difference between a resistor and a step down regulator

 

[Jidan]

A resistor decreases the voltage by a certain amount, measured in ohms. A step-down regulator brings the voltage down TO a certain amount.

That was confusing...

 

[samjc3]

to clarify, in simple terms a resistor just lowers the voltage by however many ohms. a step down regulator, on the other hand, takes whatever voltage you put in, and puts out a set amount. (like a 7805, as long as the input is between 6 volts and 48v DC, it will put out 5v.)

 

[grossaffe]

yuck, such ugly explanation. Voltage isn't measured in ohms, its measured in volts. adding a resistor reduces the voltage by IR, which is Amperage times Resistance. So the amount of the voltage is changed by adding a resistor depends on the rest of the circuit.

As mentioned, a step-down regulator is meant to get you to a particular voltage. Depending on the type of step-down regulators, it can use different methods to bring the voltage down. Linear regulators like the 7805 use resistors as well as are more complicated component to achieve this result. Energy is lost in this method as heat in the resistors.
Another form of step down regulator is a switching regulator that turns the circuit on and off to achieve a lower voltage, and uses a storage element such as an inductor or capacitor to hold a voltage while the circuit is off. Its a little periodic in nature, however it is more energy efficient.

 

[Jidan]

I meant that the resistors are measured in ohms, which really confused the whole thing

 

[ToastBucket]

basically resistors step down the voltage relative to the starting voltage. Switching regulators have a constant voltage no matter what voltage you put in there (although there are some guidelines as to how much voltage the chip can take etc.) If this caused more confusion, completely disregard it.

 

[grossaffe]

basically resistors step down the voltage relative to the starting voltage. Switching regulators have a constant voltage no matter what voltage you put in there (although there are some guidelines as to how much voltage the chip can take etc.) If this caused more confusion, completely disregard it.

They step voltage down relative to the voltage and the current. There are three variables in the equation. If you measured the voltage of the source and the current, then you could calculate the extra resistance needed to step the voltage down to the desired level, however it wouldn't be regulated like voltage from a step-down regulator.

 

[superthorn96]

Ok guys

i finally finished my cst testing so i am getting back to work on my portable

i know i can use a TI PTH 08000 or a 08080

so where do i buy it? ( a link to a page would be helpful )


And i went to fry's and got a 2k ohm resistor

but.... it was 1/2w

so where can i get 2k ohm 1/4 resistor

thanks for your time

 

[ToastBucket]

I dont think that 1/4 thing matters. Here's the ti chip, http://focus.ti.com/docs/prod/folders/p ... 8000w.html (just click the free samples button) . When you get it just test it with a multimeter with that resistor you have and see if you get 3-3.3v out of it.

 

[superthorn96]

so..... the resistor wattage doesn't matter

i can use a 2kohm with 1/2watt

 

[ToastBucket]

yup

 

[superthorn96]

Ok... i know i am going to need a power switch because

the ps1 screen turns on when the n64 does, but it still takes power while its off

so.. what kind of power switch sould i get.

also i know i only solder the postive. right?

also do i only need to do it for the screen or both the n64 and screen

thanks

 

[ToastBucket]

Get a DPDT switch and wire it up with SS's Play and Charge switch diagram (Megastickied in the voltage section). Have one of the 7.4v lines coming from it go to the pth08000 and the other 7.4v line go to screen and N64 7.4v line. You'll know what I'm talking about when you see his switch. If not, I'll make a full diagram for you with that switch. I <3 makin me some diagrammas!

 

[superthorn96]

well... that confused me a bit... tb.. i thought it would be more like this

\

( forgot the neg to screen )

i wanted to know what kind of power switch to get

 

[Basement_Modder]

SP-DT submini slide switch.

DP-DT if you use SS's diagram.

 

[superthorn96]

i got an

SPST Rocker Switch

Rated 10A at 125VAC
6A at 250VAC

Requires at 3/4'' mounting hole

it looks similar to this

would this be OK?