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.