MAX1559 Datasheet, PDF (1/14 Pages) Maxim Integrated Products – 5-Output Power-Management IC For Low-Cost PDAs

19-2962; Rev 1; 10/03
EVAALVUAAILTAIOBNLEKIT
5-Output Power-Management IC For
Low-Cost PDAs
General Description
The MAX1559 is a complete power-management chip
for low-cost personal digital assistants (PDAs) and
portable devices operating from a 1-cell lithium-ion
(Li+) or 3-cell NiMH battery. It includes all the regula-
tors, outputs, and voltage monitors necessary for small
PDAs while requiring a bare minimum of external com-
ponents. Featured are four linear regulators, a DC-DC
boost converter for LCD bias, a microprocessor reset
output, and low-battery shutdown in a miniature QFN
package. For a compatible Li+ charger for both USB
and AC adapter inputs, refer to the MAX1551*.
The four linear regulators feature PMOS pass elements
for efficient low-dropout operation. A MAIN LDO sup-
plies 3.3V at 500mA. A signal-detect (SD) card-slot out-
put supplies 3.3V at 400mA. The COR1 LDO outputs 1V
at 250mA, and the COR2 LDO supplies 1.8V at 30mA.
The SD output and COR2 LDO have pin-controlled
shutdown. For other output-voltage combinations, con-
tact Maxim.
The DC-DC boost converter features an on-board MOSFET
and True Shutdown™ when off. This means that during
shutdown, input power is disconnected from the induc-
tor so that the boost output falls to 0V rather than
remaining one diode drop below the input voltage.
A µP reset output clears when the MAIN LDO achieves
regulation to ensure an orderly start. Thermal shutdown
protects the die from overheating.
The MAX1559 operates from a 3.1V to 5.5V supply and
consumes 50mA of no-load supply current. It is pack-
aged in a 1.3W, 16-pin thin QFN with a power pad on
the underside of the package. The MAX1559 is speci-
fied for operation from -40°C to +85°C.
Applications
PDAs
Organizers
Cellular and Cordless Phones
MP3 Players
Hand-Held Devices
o Minimal External Components
o 3.3V, 500mA MAIN LDO
o 3.3V, 400mA SD Card Output
o 1V, 250mA Core LDO
o 1.8V, 30mA Second Core LDO
o High-Efficiency LCD Boost
o LCD 0V True Shutdown when Off
o 50µA Quiescent Current
o 3.1V to 5.5V Input Range
Features
PART
MAX1559ETE
Ordering Information
TEMP RANGE
-40°C to +85°C
PIN-PACKAGE
16 Thin QFN
Typical Operating Circuit
INPUT
3.1V TO 5.5V
IN
MAIN
3.3V, 500mA
SWIN
SDIG
MAX1559
REF
COR1
3.3V, 400mA
1.0V, 250mA
SDIG _OFF ^ON
COR2 _OFF ^ON
LCD
ON
OFF
TO MAIN
ENSD
ENC2
ENLCD
COR2
SW
LX
1.8V, 30mA
LCD 20V,
D1
1mA
True Shutdown is a trademark of Maxim Integrated Products, Inc.
*Protected by U.S. Patent #6,507,172.
RESET OUT
LFB
RS
GND
Pin Configuration appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.