LR8
The minimum capacitance required for given boot-up time is
given by the following equation:
COUT
> tBOOT
IPWM − ILIM
VHYS
where
COUT = Capacitor at LR8 output
tBOOT = Time required for supply to bootstrap
IPWM = Current used by PWM controller
ILIM = LR8 current limit (10mA min)
VHYS = PWM controller UVL hysteresis
Remember that this equation is valid only when PWM current
exceeds the LR8’s current limit.
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11/30/01rev.1