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## Xenon lamp ignition sequence

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### Xenon lamp ignition sequence

Hi,
time ago I studied the ignition circuit of a Xenon lamp (see attachments) I wanted a last information kindly, on power-up sequence:

1. Load the capacitors to a certain voltage (max 300Vcc)
2. sending the capacitor voltage across the lamp
3. active discharge trigger (lasting from 10 to 30ms) to get the lighting of the lamp

is' the right sequence?

The duration of the ignition of the lamp is equal to the duration of the discharge trigger?
tnnelectronics

Posts: 7
Joined: Thu Dec 18, 2014 1:21 pm

### Re: Xenon lamp ignition sequence

Sequence is correct (but just guessing at your particular circuit). The length of time the lamp is lighted is determined by the value of the capacitor, the peak capacitor voltage, the capacitor discharge current, and the cut-off voltage of the lamp. Not by the length of the trigger pulse. That just initiates the discharge. The trigger could be milliseconds and the lamp could be lit for only microseconds. Probably more that you want to know:
http://www.repairfaq.org/REPAIR/F_strbfaq.html

Ken
KMoffett

Posts: 190
Joined: Sun Apr 13, 2014 3:41 pm
Location: Minnesota USA

### Re: Xenon lamp ignition sequence

ok,

so if rather than wait for the lamp to turn off when the capacitor voltage falls below a certain level,
I wanted to have ignitions of X milliseconds after ignition, just remove the voltage across the lamp at a given period T (ms) Default?

that's right?
tnnelectronics

Posts: 7
Joined: Thu Dec 18, 2014 1:21 pm

### Re: Xenon lamp ignition sequence

I have seen ways in the past of cutting off the lamp current, but I can't point you to any right now. I think it used an SCR in series with the lamp, and back biased the anode/cathode to turn it off.

Ken
KMoffett

Posts: 190
Joined: Sun Apr 13, 2014 3:41 pm
Location: Minnesota USA

### Re: Xenon lamp ignition sequence

tnnelectronics

Posts: 7
Joined: Thu Dec 18, 2014 1:21 pm