Figure 5 : Application Circuit.
L9610C - L9611C
The sensing resistor RS and timing capacitor Ct
should be dimensioned according to :
RS =
VSi
2Inom (@Vs=14 V)
Ct =
2 x limitation time
KT
In normal conditions (VCC = 14 V, maximum bright-
ness) the voltage drop across the sense resistor
must be 50 mV. The current limiter intervenes
attwice the nominal current, Inom.
The timing capacitor Ct (Vct =3.5 V) must be chosen
so that the delay before intervention is twice the du-
ration of the current limitation at power-on.
The optimal value of the oscillator frequency, taking
tolerances into account, must be slightly higher than
the frequency at which lamp flicker is noticable (min
60 Hz).
The switching times are a compromise between
possible EMI and switching power losses. The rec-
ommended value for Cs is 47pF.
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