EVALUATION KIT AVAILABLE
MAX1553/MAX1554
High-Efficiency, 40V Step-Up
Converters for 2 to 10 White LEDs
General Description
Benefits and Features
The MAX1553/MAX1554 drive white LEDs in series with
a constant current to provide efficient display backlighting in cellular phones, PDAs, and other hand-held
devices. The step-up converter includes an internal
40V, low RDSON, N-channel MOSFET switch for high
efficiency and maximum battery life. The MAX1553 has
a current limit of 480mA for driving two to six white
LEDs, while the MAX1554 has a current limit of 970mA
for driving up to 10 white LEDs.
A single analog/PWM Dual Mode™ input provides two
simple means of brightness adjustment. A separate
enable input provides on/off control. Soft-start minimizes inrush current during startup.
The MAX1553/MAX1554 are available in space-saving
8-pin TDFN 3mm x 3mm packages.
• Highly Integrated and Flexible Solution for Wide
Applications
Range of Backlighting Applications
• Constant-Current Regulation for Even LED
Illumination
• Internal 40V MOSFET Switch Capable of Driving
10 LEDs
• 2.7V to 5.5V Input Voltage Range
• Analog or PWM Control of LED Intensity
• Optimized for Low Input Ripple
• Soft-Start Minimizes Inrush Current
• High Efficiency Improves Battery Life
• Up to 88% Efficiency Driving 6 LEDs
• Up to 82% Efficiency Driving 9 LEDs (20mA,
VCC = 3.6V)
• Tiny 8-Pin, 3mm x 3mm TDFN Package Saves Space
• Small, Low-Profile External Components
Cellular Phones
PDA, Palmtop, and Wireless Handhelds
Ordering Information
Color Display Backlight
PART
TEMP RANGE
PIN-PACKAGE
TOP
MARK
MAX1553ETA
-40°C to +85°C 8 TDFN 3mm x 3mm
AGX
MAX1554ETA
-40°C to +85°C 8 TDFN 3mm x 3mm
AGY
Dual Mode is a trademark of Maxim Integrated Products, Inc.
Pin Configuration
Typical Operating Circuit
TOP VIEW
2.7V TO 5.5V
INPUT
VCC
ON
OFF
LX
EN
OV
DC CONTROL
19-2875; Rev 2; 5/15
SS
1
8
LX
2
7
0V
EN
3
6
SS
BRT
BRT
GND
VCC
MAX1553
MAX1554
PWM
OR
WHITE
LEDS
4
5
FB
MAX1553
MAX1554
FB
GND
TDFN
3mm x 3mm