Need to know type of transistor

[Hippijoebob]

Hello, i am wondering what type of transistor cuts the circuit when power is supplied to the pin that regulates the flow.  Thanks.  Also, where could i buy one that works with the 360 controller voltages (1.5-2.5v).

[FOOKz™]

You want a PNP transistor then. pretty much every medium and small signal transistors use around 1.5 to 5 volts so don't worry.

A Few part common pnp transistor numbers off the top of my head are 2N3906 and i think 2N2907. So just go for the first one(2N3906), they aren't expensive at all just look them up at http://www.digikey.com

I'm curious what Exactly are your trying to build with this?

[Hippijoebob]

my idea is to put tri-color leds in the xbox guide button.  Normally blue, but if it vibrates it cuts blue and goes green.  But, if rapid fires on it cuts blue and green and just is red.  I know you can do this with  a PIC but i am lazy.

[FOOKz™]

Actually I found a 7-Color LED at Radioshack just the other day for $2.99 and it doesn't need any programming. its the simplest thing EVER! I Had to Buy all 5 of Them! it was just too good to be true. Plus im doing the same thing just im using the 7-color LED instead of your RGB LED for the middle.

there are 3 pins because the Middle Pin is the Positive Common, the bent outer lead is a "startup effect" that flashes through all it's colors and it supplies the chip inside it's power. the pin on the other side is to activate individual colors one at a time by putting a switch somewhere on the controller to "toggle" colors on or off.

Take a look here: http://www.buzzillions.com/reviews/radio-shack-high-brightness-7-color-5mm-blinking-led-reviews

[Hippijoebob]

i just did that mod first with 2 5mm leds and 1 10mm led and now im going to buy 4 3mm leds.   I drilled it out nice but the 10mm is so long that the buttons stuck down, lol.

[RDC]

You'll want an NPN type Transistor, not PNP. There are no switched negative sources in the controller to turn a PNP Transistor on. Get an NPN and use the Analog Voltage line to turn the thing on/off, it's switched and will turn it on/off with the controller, that's TP7 on the Wireless Matrix and TP8 on the Wireless CG and CG2 boards. Then wire up your LEDs to whatever + source you plan to use (the PnC battery connection is recommended as it also has power on it when a AA pack is used) then the Transistor will turn the Ground connection on/off for the LEDs.

[FOOKz™]

To light an LED with a PNP transistor, or Switch with a PNP transistor you must Bias the Output; in this case the Emitter with some sort of resistance that drops more than 0.8 Volts so its not the easy path to ground.

The Emitter then will be more negative than the Base (the Base needs to be more negative to switch the PNP)

Shorting the Base to ground across the load will bias the Base more negative than the emitter. Which switches on the transistor and lets current flow through the load and transistor.

NPN or PNP transistors can be used, it doesn't matter its how you bias them and whether or not its common collector or common emitter. I prefer NPN for switching, but in this case

i am wondering what type of transistor cuts the circuit when power is supplied to the pin that regulates the flow.

a PNP transistor is necessary.

[RDC]

Wow, 11 days is an old topic?

Correct on the PNP cutting power when power is applied, though most people are after how to turn one on and that's what I was explaining, missed that in his OP about cutting power, my bad. I'll be sure to stay away from 'old' topics in the future, even if I do have something useful to contribute.

[FOOKz™]

11 days seemed like a long time to me, forgot to look at the time stamp [not really paying attention at all]


Offtopic:
By the way RDC are you very good at designing circuits without PICs? you seem like you know your way around the xbox360 controller better than i do. Never found schematics and test point diagrams around here to find a good switched supply on a controller.

[RDC]

No worries.

I couldn't code a PIC to blink and LED, so I kinda had to figure out other ways to do some of the things I've done. The CGnome Project I worked on all that coding was done by Jam az, I did all the hardware related things, designed the board, knew what the controller needed here and there to work and such. One of my favorite ICs to use is the 4066, that thing is a gem, especially on the Matrix version controllers because of it's button layout.

The Analog Voltage line in any of the 360 controllers is a good switched + source, but it's only 1.5v to 1.6v depending on the controller version, so that's why I explained using the NPN as the switch, that way you can use the B+ and basically get the full battery voltage, minus what the Transistor knocks off of course, to power LEDs or whatever.

The Wireless Matrix has a decent 2v switched spot over on the left, but even it should be used to turn a Transistor on/off, and the CG has a 3v one at the headset connector, seems the CG2 is a tad different there for some reason though, haven't really dove into it as much as the Matrix and CG yet.

Over at XS I have all of them traced out as far as the buttons and Analog lines go. The main power points aren't too difficult to find with a meter and sitting there turning it on/off a few times, but I've never made up a list or diagram for them. The Wired controllers 5v stays on even if the controller and 360 are off, since it comes from the 5vsb in the 360, but it's Analog Voltage lines are still switched like the Wireless controllers are. You may want to have a look at the threads in the Faqs/Tuts section of 360 Case / Hardware Modding I've done, some info on PS3 controllers as well in the PS3 Case Hardware section there too I've compiled, might be useful to you for something or another. If you have something specific you'd like to work on shoot me a PM here or there and we'll see if we can figure it out.

http://forums.xbox-scene.com/index.php?showforum=132# - 360

http://forums.xbox-scene.com/index.php?showforum=341# - PS3