DER-424 Dimmable or not?

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Dear Support,


It’s worth to try whether your design DER-424,  is suitable for my application..

I am not yet familiar with your schematic, so I need some support now, for making a good start!

I wonder if dimmable is also possible in this design?

If not:

-   Can I modify it in a way that dimmable or full light only depends by the use of a triac-dimmer, or not.

Deep dimming is not necessary, let’s say between 50-100%

-   Or is there already another design, I better can use.


Thanks in advance.


No its not dimmable. For other design, I need to know what are you're detailed requirements so I can recommend correctly.


OR, you can  go to the design selector site for all the available design examples that can fit your requirement


Briefly my requirements:


- Universal voltage Input 90VAC-230VAC

- Output 48V-350 mA

- Isolated flyback

- LYTSwitch design

-Triac-dimmable; where dimmable- or full-light, depends by the use of  a dimmer. or not





We dont normally recommend universal solution for TRIAC dimming applications. LYTSwitch-4 ICs have high line version and low line version for TRIAC dimming applications. We dont have the exact DER for your output power range but you can look at these two DERS for your starting point if you decided to do separate design for low line and high line.

  Low line  dimmable design

High line dimmable design

Dear Support,


I have seen both designs you have talked about.

Separate designs for low- and highline versions is not the problem.

May be dimmable, with most important, a fast start-up and switch-off time of <100 msec, that I can put on a pcb-board of 40x40 mm or within a diameter of 60 mm, working with an output current between 330-550 mA, is within your possibilities an unrealistic demand of me.

But that’s what I am searching for!


Waiting on your comments.


Universal input dimming is impractical to do because of different characteristic of dimmers for high line and low line.  Matching impedance and timing is important to achieve a good dimming performance.  Component size and cost will not be optimized.


If you are really looking for wide range but almost close to the performance of high line and low line dimming then you can use this reference.