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| Thread ID: 94389 | 2008-10-27 07:40:00 | Voltage Regulators | pine-o-cleen (2955) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 715124 | 2008-10-27 07:40:00 | Ok, I'm building a simple LED circuit to light up my keyboard (so that I don't have to turn on the lights!) . I brought 2x these ( . dse . co . nz/cgi-bin/dse . storefront/49056ef5005b914e2740c0a87f3b0688/Product/View/Z3802" target="_blank">www . dse . co . nz) and I want to connect them to a USB port for power . Now here is the problem! USB is obviously 5v, and these are 3 . 0v min 3 . 8v max . I have worked out that I will need a voltage regulator but which one? How do I choose one? |
pine-o-cleen (2955) | ||
| 715125 | 2008-10-27 07:46:00 | Why dont you buy a backlit KB ? | Speedy Gonzales (78) | ||
| 715126 | 2008-10-27 07:52:00 | Ok, I'm building a simple LED circuit to light up my keyboard (so that I don't have to turn on the lights!). I brought 2x these (www.dse.co.nz) and I want to connect them to a USB port for power. Now here is the problem! USB is obviously 5v, and these are 3.0v min 3.8v max. I have worked out that I will need a voltage regulator but which one? How do I choose one? No you don't need a voltage regulator at all, you need a current limiting series resistor. Otherwise the LED may/will go poof! Try something like 82 ohms feeding each LED. Dick Smith tells you how :) www.dse.co.nz |
Terry Porritt (14) | ||
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