MAX16836EVKIT+ Maxim Integrated Products, MAX16836EVKIT+ Datasheet - Page 8
![no-image](/images/manufacturer_photos/0/4/417/maxim_integrated_products_sml.jpg)
MAX16836EVKIT+
Manufacturer Part Number
MAX16836EVKIT+
Description
KIT EVAL FOR MAZ16832 LED DRIVER
Manufacturer
Maxim Integrated Products
Specifications of MAX16836EVKIT+
Current - Output / Channel
350mA
Outputs And Type
1, Non-Isolated
Voltage - Output
5V
Features
Dimmable, Extra 5V Output
Voltage - Input
6.5 ~ 40V
Utilized Ic / Part
MAX16836
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Figure 4 shows PWM dimming operation for the
MAX16836 with an ICM7555 timer. The ICM7555 pro-
vides 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
V
the LEDs light up to full brightness. See the ICM7555
data sheet for formulas to calculate the dimming fre-
quency and the duty cycle.
High-Voltage, 350mA, High-Brightness LED
Driver with PWM Dimming and 5V Regulator
Figure 4. PWM Dimming Operation with ICM7555 Timer
Figure 5. LED Current Thermal Foldback with an NTC Thermistor
8
STOP
_______________________________________________________________________________________
. The PWM dimming operation is disabled and
C3
R3
STOP
DIS
TH
TRG
R2
V
IN
Two Brightness Levels for
STOP
TAIL
ICM7555
C1
is present, DIM is pulled up to
IN
GND
OUT
PWM DIMMING
TAIL/STOP Lights
D3
R1
D4
*R4 ≤ 300kΩ
D5
IN
EN
DIM
GND
R4*
MAX16836
D1
D2
C1
With a minimum number of external components, the
MAX16836 provides LED current thermal foldback
using a negative temperature coefficient (NTC) thermis-
tor. Figure 5 shows a thermistor connected to V5 and
the CS+ of the MAX16836. As the temperature increas-
es, the voltage drop across R2 increases causing the
LED current to decrease.
(assuming I
OUT
CS+
CS-
IN
EN
DIM
GND
I
V5
LED
=
MAX16836
[
V
RT
SENSE
C2
< < I
LED Current Thermal Foldback
LED
−
RT
[
R
OUT
CS+
CS-
2
V5
).
R2
/(
R
+5V REG
2
+
RT
C2
LEDs
)]
R1
×
V
5
]
LEDs
R
×
SENSE
⎛
⎜
⎝
R
R R
T
1
+
R
T
2
⎞
⎟
⎠