MAX16838ATP/V+ Maxim Integrated, MAX16838ATP/V+ Datasheet - Page 18

• Manufacturer Part Number: MAX16838ATP/V+
• Description: LED Lighting Drivers Integrated 2-Channel High-Brightness LED Drivers with High-Voltage DC-DC Controller
• Manufacturer: Maxim Integrated

Specifications of MAX16838ATP/V+

• Input Voltage: 4.75 V to 40 V
• Maximum Supply Current: 3.1 mA
• Power Dissipation: 2051 mW

Integrated, 2-Channel, High-Brightness LED Driver
with High-Voltage Boost and SEPIC Controller
Figure
3) There are two loops in the power circuit that carry
18
high-frequency switching currents. One loop is
when the MOSFET is on—from the input filter
capacitor positive terminal, through the inductor, the
internal MOSFET, and the current-sense resistor, to
the input capacitor negative terminal. The other loop
is when the MOSFET is off—from the input capacitor
positive terminal, through the inductor, the rectifier
diode, output filter capacitor, to the input capaci-
tor negative terminal. Analyze these two loops and
make the loop areas as small as possible. Wherever
_____________________________________________________________________________________
5. Boost-Buck Configuration
V
IN
R1
R2
EN
EN
C
VCC
C
IN
C
R
COMP
C
COMP
R
DRV
DRV
C
1
EN
CFB
V
DRV
DIM
COMP
CC
V
GND
DD
IN
SGND
MAX15054
D
MAX16838
1
GATE
HI
PGND
HDRV
BST
LX
LEDGND
NDRV
DRAIN
OUT2
C
OUT1
ISET
BST
FLT
OV
CS
RT
4) Connect the power ground plane for the constant-
Q1
D
possible, have a return path on the power ground
plane for the switching currents on the top layer
copper traces, or through power components. This
reduces the loop area considerably and provides
a low-inductance path for the switching currents.
Reducing the loop area also reduces radiation dur-
ing switching.
current LED driver part of the circuit to LEDGND as
close as possible to the device. Connect SGND to
PGND at the same point.
2
R
ISET
L
R
RT
R
D3
CS
R1
R2
OV
OV
C
OUT
LED
STRINGS