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| Stormrider:
For a wooden control panel with a psx pad hack, how could I add a led that turns red when the panel is plugged into the adapter and the computer is on? |
| DaOld Man:
If the psx hack has +5vdc and ground, just wire the led between those two points. You will need to put a 330 ohm resistor in one lead of the led. I dont really know about the psx pad, so i cant elaborate more than that. |
| Franco B:
Won't the resistor value depend on the LED? The LEDs im using at the moment require a 100ohm resistor in series. You may want to use a panel mount LED similar to these for a nice clean install. |
| DaOld Man:
Yes it would depend on how much current the led draws. I use 330 as a general resistor. It works with most leds that draw approx 20 ma at 5 volt. To choose the resistor for the led: Vs-Vd/LedIc =Rx Whereas: Vs=supply voltage (5 in this case) Vd= led voltage drop LEDIc= current draw of the Led Rx= resistor in ohms. If the pulls 10 ma and drops 2.1 volts then: 5-2.1=2.9 2.9/.010=290 ohms So yeah, you are right 330 would be a little high. If the led draws 20 ma (probably most likely), then a 145 ohm resistor will be needed. You just need to check the specs on your led before choosing the resistor. |
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