
Ultra-High-Efficiency White
LED Drivers
L
V IN
C IN
IN
FB
STEP-UP
CONTROLLER
LX
OUT
C OUT
MAX1984
MAX1985
MAX1986
CURRENT
SENSE
GND
UVLO
COMP
MIN
EN1
IREF
EN2
IREF
LD1
LDG
LD2
LDG
LD1
LD2
2.4V
REF AND
BIAS
EN3
IREF
LD3
LDG
LD3
BLOCK
C REF
REF
EN4
LD4
LD4
SHUTDOWN
IREF
LDG
MODE
EN5
LD5
LD5*
DIMMING
CONTROL
BITA
BITB
BITC
DIMMING
CONTROL
BLOCK
IREF
IREF
EN6
IREF
LDG
LD6
LDG
LD6*
SETI
R SETI
EN7
IREF
EN8
LD7
LDG
LD8
LD7**
LD8**
LED SELECT
SEL
LOGIC
EN [8:1]
IREF
LDG
LDG
*MAX1984 AND MAX1985 ONLY.
**MAX1984 ONLY.
Figure 2. System Functional Diagram
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