Simple Universal Speaker Delay Using A Triac

Member
Joined 2011
Paid Member
I think I figured it out. Attached is the model that includes all three LEDs in series. Running it in spice showed acceptably small current ripple on each LED - from 8.7mA to 10.5mA. Turn off delay should be short too - because of 47uf cap.
 

Attachments

  • delay-2n3904.asc
    2.1 KB · Views: 52
  • sch-2.PNG
    sch-2.PNG
    8.4 KB · Views: 103
  • sch-r1.3.PNG
    sch-r1.3.PNG
    25.8 KB · Views: 104