MAX16839 Datasheet, PDF (7/11 Pages) Maxim Integrated Products – High-Voltage, Linear High-Brightness LED Driver with Open-LED Fault Detect

High-Voltage, Linear High-Brightness LED
Driver with Open-LED Fault Detect
Detailed Description
The MAX16839 programmable current regulator oper-
ates from a 5V to 40V input voltage range and features
an open-drain, constant current-sink output capable of
sinking up to 100mA. The MAX16839 directly withstands
automotive load-dump events of up to 45V.
A single resistor-programmable output current and on-
board pass element minimize the number of external
components while providing Q5% output current accuracy.
The MAX16839 includes a dimming input that controls
the duty cycle of the output current, allowing a wide LED
dimming range to be implemented. In addition, the dim-
ming input functions as an on/off control of the output
current. In multiple LED-string applications, the dimming
input synchronizes the LED current-sink turn-on, ensur-
ing simultaneous brightness in LED strings.
Additional features include thermal protection and an
open-LED detection output that can turn off multiple LED
strings simultaneously. See Figure 1.
Open-LED Detection and
Fault Event Status Memory
The MAX16839 has an integrated open-LED detection
that reduces external components required to imple-
ment this function. The following conditions enable the
open-LED detection feature:
U FLTS not connected to ground
U VIN > VINTH (7.38V) (typ)
U Thermal Shutdown Inactive
U V_DIM = High
IN
30µA
DIM
1mA
THERMAL
SHDN
5V REG
5V
IREG
REFERENCE
GENERATOR
ENABLE
MAX16839
FAULT
OPEN-LED
DETECT
GND
SINK
CS
IN 15V CLAMP
2.8mA
FLTS
Figure 1. Internal Block Diagram
_______________________________________________________________________________________   7