MAX16832A_12 Datasheet, PDF (1/10 Pages) Maxim Integrated Products – 2MHz, High-Brightness LED Drivers with Integrated MOSFET and High-Side Current Sense

19-4140; Rev 5; 3/12
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2MHz, High-Brightness LED Drivers with
Integrated MOSFET and High-Side Current Sense
General Description
The MAX16832A/MAX16832C step-down constant-cur-
rent high-brightness LED (HB LED) drivers provide a
cost-effective design solution for automotive
interior/exterior lighting, architectural and ambient light-
ing, LED bulbs, and other LED illumination applications.
The MAX16832A/MAX16832C operate from a +6.5V to
+65V input voltage range and can provide an output
current up to 700mA, if operated up to a temperature of
+125°C, or up to a 1A if operated up to a temperature
of +105°C. A high-side current-sense resistor adjusts
the output current, and a dedicated pulse-width modu-
lation (PWM) input enables pulsed LED dimming over a
wide range of brightness levels.
These devices are well suited for applications requiring
a wide input voltage range. The high-side current sens-
ing and an integrated current-setting circuitry minimize
the number of external components while delivering an
average output current with ±3% accuracy. A hysteretic
control method ensures excellent input supply rejection
and fast response during load transients and PWM dim-
ming. The MAX16832A allows 10% current ripple, and
the MAX16832C allows 30% current ripple. Both
devices operate up to a 2MHz switching frequency,
thus allowing the use of small-sized components.
The MAX16832A/MAX16832C offer an analog dimming
feature that reduces the output current by applying an
external DC voltage below the internal 2V threshold volt-
age from TEMP_I to GND. TEMP_I also sources 25µA to
a negative temperature coefficient (NTC) thermistor con-
nected between TEMP_I and GND, thus providing an
analog thermal-foldback feature that reduces the LED
current when the temperature of the LED string exceeds
a specified temperature point. Additional features
include thermal-shutdown protection.
The MAX16832A/MAX16832C operate over the -40°C to
+125°C automotive temperature range and are available
in a thermally enhanced 8-pin SO package.
Applications
Architectural, Industrial, and Ambient Lighting
Automotive RCL, DRL, and Fog Lights
Heads-Up Displays
Indicator and Emergency Lighting
MR16 and MR111 LED Lights
Pin Configuration appears at end of data sheet.
Features
o High-Efficiency Solution
o 6.5V to 65V Input Voltage Range
o Output Current Up to 1A
o On-Board 65V, 0.45Ω Power MOSFET
o Hysteretic Control: Up to 2MHz Switching
Frequency
o ±3% LED Current Accuracy
o 200mV Current-Sense Reference
o Resistor-Programmable Constant LED Current
o Integrated High-Side Current Sense
o Thermal-Foldback Protection/Linear Dimming
o Thermal-Shutdown Protection
o Available in a Thermally Enhanced 8-Pin SO
Package
o -40°C to +125°C Operating Temperature Range
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX16832AASA+
-40°C to +125°C 8 SO-EP*
MAX16832CASA+
-40°C to +125°C 8 SO-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Typical Application Circuit
D1
HB LEDs
VIN
RSENSE
L1
C2
1 _CS
TEMP_I ⁸
NTC*
ON
2 _IN
DIM ⁷
OFF
MAX16832A
C1
3
MAX16832C
GND
LX ⁶
4 _PGND
LX ⁵
*OPTIONAL
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.