Timeline for How can I best control various high power LEDs without using PWM
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Apr 27, 2015 at 13:06 | vote | accept | Uli | ||
| Apr 26, 2015 at 21:18 | comment | added | James Waldby - jwpat7 | (1) Re "How many LEDs", see example power calcs, added at end. (2) Re "high max resistance" for dimming, see added note: "When V1 is set to less than VBE, no current will flow through the LEDs". Ie, low V1 voltage turns LEDs off, rather than a large resistor doing so. | |
| Apr 26, 2015 at 21:15 | history | edited | James Waldby - jwpat7 | CC BY-SA 3.0 |
add power calcs examples
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| Apr 26, 2015 at 15:41 | comment | added | Uli | Thank you very much for your response! Please bear with me, I am far from an electrical engineer. If I understood you correctly, the basic idea is to use transistors (Q) to create the dynamic resistance for the LEDs. The resistance of the transistors in turn is controlled through the digipot (V1). How many LEDs could I wire to a single transistor without burning it? Ideally I would like to wire 8 LEDS (one row) per transistor. Is there a specific transistor you would recommend? I guess I need high max resistance to be able to dim the LEDs to almost off. | |
| Apr 25, 2015 at 17:32 | history | edited | James Waldby - jwpat7 | CC BY-SA 3.0 |
add R1, R2 calcs for voltage divider
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| Apr 25, 2015 at 7:58 | history | answered | James Waldby - jwpat7 | CC BY-SA 3.0 |