MAX16823_15 Datasheet, PDF (7/12 Pages) Maxim Integrated Products – High-Voltage, 3-Channel Linear High-Brightness LED Driver with Open LED Detection

MAX16823
Block Diagram
IN
IN
IN
High-Voltage, 3-Channel Linear High-Brightness
LED Driver with Open LED Detection
BANDGAP
REG
I_REG
UVLO
IN
OUT1
CS1
GND
DIM1
MAX16823
DIM2
THERMAL
SHUTDOWN
DIM3
LEDGGOOD
LGC
LEDGOOD
DETECTOR
I_REG
I_REG
IN
OUT2
CS2
IN
OUT3
CS3
Pulse-Dimming Inputs (DIM_)
The MAX16823 features pulsed or chopped-current
dimming inputs (DIM_) to chop the LED current and to
adjust the brightness. DIM_ also serves as an active-high
enable input. A logic-low at DIM_ turns off OUT_ and
a logic-high turns on OUT_. If the signal at DIM stays
low more than the programmed LEDGOOD delay time,
LEDGOOD goes low (Figure 1).
Two Brightness Levels for TAIL/STOP Lights
Figure 2 shows the PWM dimming operation for the
MAX16823 with an ICM7555 timer. The ICM7555 provides
an adjustable duty cycle using two external resistors and
a capacitor. In TAIL operation, the output of the ICM7555
feeds into DIM and lights up the LEDs. The LED’s
brightness depends on the duty cycle of the ICM7555.
When V_STOP is present, DIM is pulled up to V_STOP. The
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