MAX16818_09 Datasheet, PDF (1/25 Pages) Maxim Integrated Products – 1.5MHz, 30A High-Efficiency, LED Driver with Rapid LED Current Pulsing

19-0666; Rev 2; 3/09
EVAALVUAAILTAIOBNLEKIT
1.5MHz, 30A High-Efficiency, LED Driver
with Rapid LED Current Pulsing
General Description
The MAX16818 pulse-width modulation (PWM) LED dri-
ver controller provides high-output-current capability in
a compact package with a minimum number of external
components. The MAX16818 is suitable for use in syn-
chronous and nonsynchronous step-down (buck)
topologies, as well as in boost, buck-boost, SEPIC, and
Cuk LED drivers. The MAX16818 is the first LED driver
controller that enables Maxim’s patent-pending technol-
ogy for fast LED current transients of up to 20A/µs and
30kHz dimming frequency.
This device utilizes average-current-mode control that
enables optimal use of MOSFETs with optimal charge
and on-resistance characteristics. This results in the
minimized need for external heatsinking even when
delivering up to 30A of LED current. True differential
sensing enables accurate control of the LED current. A
wide dimming range is easily implemented to accom-
modate an external PWM signal. An internal regulator
enables operation over a wide input voltage range:
4.75V to 5.5V or 7V to 28V and above with a simple
external biasing device. The wide switching frequency
range, up to 1.5MHz, allows for the use of small induc-
tors and capacitors.
The MAX16818 features a clock output with 180° phase
delay to control a second out-of-phase LED driver to
reduce input and output filter capacitors size or to mini-
mize ripple currents. The MAX16818 offers programma-
ble hiccup, overvoltage, and overtemperature protection.
The MAX16818ETI+ is rated for the extended tempera-
ture range (-40°C to +85°C) and the MAX16818ATI+ is
rated for the automotive temperature range (-40°C to
+125°C). This LED driver controller is available in a
lead-free, 0.8mm high, 5mm x 5mm 28-pin TQFN pack-
age with exposed paddle.
Applications
Front Projectors/Rear Projection TVs
Portable and Pocket Projectors
Automotive, Bus/Truck Exterior Lighting
LCD TVs and Display Backlight
Automotive Emergency Lighting and Signage
Features
o High-Current LED Driver Controller IC, Up to 30A
Output Current
o Average-Current-Mode Control
o True-Differential Remote-Sense Input
o 4.75V to 5.5V or 7V to 28V Input Voltage Range
o Programmable Switching Frequency or External
Synchronization from 125kHz to 1.5MHz
o Clock Output for 180° Out-of-Phase Operation
o Integrated 4A Gate Drivers
o Output Overvoltage and Hiccup Mode
Overcurrent Protection
o Thermal Shutdown
o Thermally Enhanced 28-Pin Thin QFN Package
o -40°C to +125°C Operating Temperature Range
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX16818ATI+
-40°C to +125°C 28 TQFN-EP*
MAX16818ETI+
-40°C to +85°C 28 TQFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Simplified Diagram
7V TO 28V
IN
EN
ILIM
Q1
DH
MAX16818
Q2
DL
OVI
CSP
CLP
PGND
C1
V_LED
L1
C2
Q3
R1
Pin Configuration appears at end of data sheet.
HIGH-FREQUENC.Y
PULSE TRAIN
NOTE: MAXIM PATENT-PENDING TOPOLOGY
________________________________________________________________ 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.