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Re: CGS114 Serge DUSG LEDs and driver questions

2016-05-17 by Ken Stone

I prefer to use high-brightness LEDs at very low currents. The resistor needs to be selected via experiment, though, as not all LEDs are equal. To test, connect your +VE through two diodes to the LED, then the LED resistor. Select for a value that doesn't dazzle you. I find resistors are usually in the range of 4k7 to 10k.

Using a lower current for your LED puts less switching noise on your power rails, as well as reducing the overall current required.

The driver circuit should be okay as it is.



On Tue, May 17, 2016 at 6:31 PM, guymccusker@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

I'm about to build my first CGS114 DUSG. I've seen a few people mention that the module runs better with low-current LEDs rather than standard ones.


First obvious question: is that true?


Second question: if it is a good idea to use low current LEDs, what changes are needed to the driver circuitry? Obviously a higher value current-limiting resistor would be in order, but what about the base drive resistor?


I am keen to get good values from the outset because I hate desoldering and I understand the boards can be delicate too. Any hints will be very much appreciated!




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>

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