MAX16814EVKIT+ Maxim Integrated Products, MAX16814EVKIT+ Datasheet - Page 20

• Manufacturer Part Number: MAX16814EVKIT+
• Description: KIT EAL FOR MAX16814
• Manufacturer: Maxim Integrated Products

Specifications of MAX16814EVKIT+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Connect a resistor R
Figure 7 for controlling the LED string current using an
external control voltage. The MAX16814 applies a fixed
1.23V bandgap reference voltage at SETI and measures
the current through SETI. This measured current mul-
tiplied by a factor of 1220 is the current through each
one of the four constant current-sink channels. Adjust
the current through SETI to get analog dimming func-
tionality by connecting the external control voltage to
Integrated, 4-Channel, High-Brightness LED
Driver with High-Voltage DC-DC Controller
Figure 5. SEPIC Configuration
20
_____________________________________________________________________________________
Analog Dimming Using External
C3
SETI2
C
R
COMP
COMP
C4
R5
to the SETI input as shown in
4.75V TO 40V
C1
V
IN
EN
V
DRV
DIM
COMP
CC
IN
Control Voltage
NDRV
SGND
R
SCOMP
L1
MAX16814
CS
PGND
N
R
CS
C
LEDGND
S
L2
OVP
SETI through the resistor R
in the LED current with the control voltage is linear and
inversely proportional. The LED current control range
remains between 20mA to 150mA.
Use the following equation to calculate the LED current
set by the control voltage applied:
D1
OUT1
OUT2
OUT3
OUT4
RSDT
SETI
FLT
RT
R2
R1
R
T
I
R
OUT
SETI
C2
=
R4
R
1500
SETI
R3
UP TO 40V
+
(
1.23 V
SETI2
R
V
SETI2
CC
−
. The resulting change
C
)
×
1220