| ??? 03/27/09 11:06 Read: times |
#163901 - I did say, "Maybe Unlikely"... Responding to: ???'s previous message |
Ap Charles said:
PWM Dimming with SCR ?? , You cannot control the Gate of an SCR with a PWM signal , once lached you will loose controle from its gate. Andy Neil said:
Unless the [DC] supply is pulsed in some way, to allow the SCRs to turn off... Ap Charles said:
never heard of doing this with DC. Well, I've never actually seen it done - which is why I titled my post "Maybe Unlikely, but..." - but it is a possibility, isn't it? "Phase-angle control" is, essentially, a form of pulse-width modulation (PWM) - where the "pulse" is not rectangular (it's half a sinusoid). Maybe his "DC" supply is just unsmoothed, rectified AC...? Again, it needs clarification from the OP. |
| Topic | Author | Date |
| PWM LED dimming | 01/01/70 00:00 | |
| Can you be more specific? | 01/01/70 00:00 | |
| PWM Dimming with SCR?? | 01/01/70 00:00 | |
| Maybe Unlikely, but... | 01/01/70 00:00 | |
| Oh that is universally known | 01/01/70 00:00 | |
| I did say, "Maybe Unlikely"... | 01/01/70 00:00 | |
| then it better be a high frequency | 01/01/70 00:00 | |
AC-driven LED ropes | 01/01/70 00:00 |