FLC21 STMicroelectronics, FLC21 Datasheet - Page 5

• Manufacturer Part Number: FLC21
• Description: Low power fire lighter circuit
• Manufacturer: STMicroelectronics

RS RESISTANCE CALCULATION
The Rs resistance allows, in addition with the
capacitance C, the spark frequency to be adjusted
and the current supplied by the mains to be limited.
This resistance allows the thyristor triggering in
Rs
Fig. 4: Spark frequency versus Rs and C.
The couple Rs/C can be chosen with the previous
curve. Keep in mind the Rs maximum limit for
which the system would not work when the AC
mains is minimum.
The maximum Rs value is equal to:
* : see fig 1
50
30
20
10
max
10
F (Hz)
12
(
V
AC
15
min.
18
FLC21-135A
2
Rs (k )
)
22
[
V
BO
Vdc=300V, Vbo=150V, Tamb=25°C
k I
max .(
27
.
BO
33
1
*
39
T T
.(
47
amb
25
any requested cases. In the worst case scenario,
the system must fire when the a.c. line voltage is
minimum while the breakdown voltage V
the current I
))]
BO
of the FLC are maximum.
FLC21-135A
BO
and
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