Crap, you’re absolutely right; I switched the emitter and collector pins in my description. The ground from the LEDs and the inverter go to the collector pin, and the emitter pin goes to the PCB ground and - terminal of the batteries. Ill be editing my post now to correct.
Then skip it. I just like anchoring things down to known values. I prefer to keep from having any pins floating under any circumstances if I can help it. If the PSX cable, if it’s unplugged, is floating; no voltage of any kind. This also means it is susceptible to noise, random EMI from induction. This noise will show up as a change in voltage on the base pin of the transistor. It may go nowhere, it may do nothing, it may be enough to bias the transistor and turn it on for a split second; Im not sure. Like I said, I suck at analog. What I do know for certain is that by tying the pin to ground, I can make damn sure there is 0 voltage on the floating base pin, and average EMI won’t change that. So, 100% certain the switch will be off if the cable is unplugged.
Damn I should not type when tired. Hope that makes some sense.
Hey Toodles, it worked! The LEDs lit up like a charm powered by the Dual Shock pcb analog light. Though I only did one LED. I want to try all 4 at once, but am I risking blowing out the PS2 controller ports by doing this? =B
It’s crystal clear now. Thanks for the clarification.
If I find time in the next few days, I’ll have a go at doing a vector-based schematic of version 2.0 of this circuit. Maybe even offer an alternative design of it without batteries (the problem is the choice and availability of ready-made step-up converter ICs and weakness of available current). This kind of mod would be so much easier/cleaner on systems providing +5V, thru USB for instance.
This is version 2 of TingBoy’s Light-Up on button activation schematic.
Some extra components are used to extend battery life. Q1 is a 2N2222 transistor.
The resistor just before the LED can probably be changed to a 100 Ohms one or a bit lower for extra brightness (or at least that’s what my calculations show).
Thanks for the schematic harry! Very nice job. I’ll put it in the first post as soon as the fix is done.
Stopped by Fry’s Electronics yesterday. I was lucky enough to find the last 2n2222 in the store and the last batch of 20k ohm resistors, but no 5k resistors. I’ll have to stop by another one today or something =P. Would it be safe to use 4.7k, 5.1k, or 5.6k resistors instead of just 5k?
Ok, well, I finally decided to do the mod, but I came across a problem. When the pcb is powered, it works fine. When the pcb isn’t powered, all the LEDs light up when pressed 1 or more buttons are pressed. I’m guessing I need something higher than 20k?
Edit: So, I took out a battery and found out that the buttons don’t work. I connected the ends of the battery holder and found out it works. So, I’m guessing as long as a battery is there, dead or otherwise, to complete the circuit, the buttons will work?
Then theres some sort of connection inside the PCB between the button signal lines and the power. If you have a spare diode of any kind, put it between the PSX +V line and the transistor base pin. Before or after the resistor, doesn’t matter. The stripe mark on the diode should be the end closest to the transistor.
Sure. Just be careful of the current you’re using. USB devices have to tell the host how much power they’ll be needing, either 100mA or 500mA. Almost all of them request 100mA, and if your doohickey pulls more than that, the USB host is within its right to shut it down and disconnect the device.
And you’re sure the LEDs are going from the inverter output to the collector pin of the resistor? They are NOT connected to ground, correct? Sorry for being a pedantic ass, but if they’re connected to the transistor, the only way they could light is if the transistor is biased, and I’m just not seeing how that could be. I could see how it could happen if the LEDs were connected to ground and the inverter used the grounded input pin for the current to flow out of, but that wouldn’t allow the LEDs to light if the LEDs went to the collector pin.
If you have a multimeter, can you check the voltage at the base pin of the transistor (black probe on ground, red probe on base pin, multimeter set to voltage) both when the button is pressed (LEDs lit) and when the button is not pressed (LEDs not lit), with the PSX cable NOT plugged in?
I’m pretty sure my wiring’s correct. It could possibly be the transistor. All of Fry’s resistors, capacitors, transistors, etc are all from NTE and NTE uses different model numbers. I had to look up the equivalent from some huge book they had lying there. Their equivalent of a 2n2222 was a NTE123A
No multimeter. I need to find a decent one for a decent price =\
Edit: I just noticed that when I plug in my stick into my PS2 with the batteries in, the LEDs light up VERY slightly. It’s a very dim glow, so I didn’t notice it at first. It doesn’t even matter if the PS2 is off/on/unplugged. It just glows.
The base-emitter junction already has a voltage drop, so forget the diode idea. However, yes, you should get a multimeter.
The NTE123A looks like it should work fine from the datasheet.
Disconnect the resistor between the base and the emitter and test again. It shouldnt be a problem, but the transistor should not activate if the base pin is floating.
What’d be really nice is checking the current going to the base pin, but you’d definitely need a multimeter for that. Im just having a difficult time understanding how the LEDs can light without a path to ground. If the LEDs are connected to the transistor right, then the transistor would have to be getting current through the base pin in order for the LED power to get to ground. So, without a multimeter, the first thing I’d suggest is checking the stuff going to the base pin. Remove the resistor connecting it to the emitter pin and test. While you’re there, eyeball it to make sure the only other thing going to the base pin is from the PSX power line. Test; if it stops glowing, then we have proof the base-emitter resistor was a bad idea. If it still glows, then disconnect the base pin from the power wire and retest; if it still glows, the transistor got bjorked somehow. If the glowing stops, then we know that some current is still getting to the PCB. Reconnect the power line to the base pin and check the diode to the battery connection to make sure the diode is pointing the right way (the stripe should be on the end connected to the batteries, NOT the end connected to the PSX power line). If the diode’s ok, then disconnect the QD’s going to the buttons. If the glowing stops when all of the QD’s are removed, then we know power is coming through those inputs; let me know and I’ll figure out how to get around it, probably with a few cheap signal diodes. If it still glows, then your stick is possessed and let me know to see if I can find an exorcism ritual for you to try.
If you’re willing to keep checking stuff, I’m willing to work with ya through it. Sorry it didn’t work first time.
I’ve been following this thread very closely. I’ve seen LED driver devices on the net such as the LED-WIZ and the ultimarc pac-drive to control and power the leds from USB. However when plugged into a USB host without software backend, the LEDS are permanently on.
Just wondering if you can somehow rig it to use the microswitches from the buttons to determine when to light on and off in sync with the buttons as is described in this thread.
Powering the device isnt the issue here, the issue is to make it use the button’s microswitch to enable the LED’s as well. The buttons are Sanwa Iluminated Chrome buttons from gremlin-solutions.co.uk , they really do look awesome. The LED driver im using is the ultimarc pac-drive.
Any diagrams would be great to get this to work with the LEDs and an xbox 360 PCB/hori ex2 pcb.
Thanks in advance! I appreciate the time and effort of all the modders out there helping out us new guys.
I just realized that I forgot to mention that I don’t have a diode in there since the slight glow didn’t really bother me, but I’ll go buy one and put it in when I get the chance to. I’ll go do the tests now =)
Edit: Ok, I rechecked my previous statements. Apparently, the slight glow only happens when the PCB is plugged into a port, but isn’t powered (also happens with converters). When I do power on the machine and the PCB is powered by the console, the glow disappears and the stick works as it should. So, quick summary.
PCB not powered, not plugged in - LEDs are completely off. All 6 buttons light up when 1 of the face buttons are pressed.
PCB not powered, plugged in - Slight glow coming from LEDs. All 6 buttons still light up when 1 of the face buttons are pressed.
PCB powered, plugged in - LEDs are completely off. Buttons light up as they should when pressed.
Edit # 2: Ok. I just tested everything you mentioned. The glow is still there even after unplugging it from the power line and taking off all of the QDs.
