LM3424 Datasheet, PDF (29/50 Pages) National Semiconductor (TI) – Constant Current N-Channel Controller with Thermal Foldback for Driving LEDs

Design Example
DESIGN #1 - BUCK-BOOST Application
SPECIFICATIONS
N=6
V_LED = 3.5V
r_LED = 325 mΩ
V_IN = 24V
V_IN-MIN = 10V
V_IN-MAX = 70V
f_SW = 500 kHz
V_SNS = 100 mV
I_LED = 1A
Δi_L-PP = 700 mA
Δi_LED-PP = 12 mA
Δv_IN-PP = 100 mV
I_LIM = 6A
V_TURN-ON = 10V
V_HYS = 3V
V_TURN-OFF = 40V
V_HYSO = 10V
T_BK = 70°C
T_END= 120°C
t_TSU = 30 ms
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