Rainbow Electronics MAX1524 - Manual

General Description
The MAX1522/MAX1523/MAX1524 are simple, compact
boost controllers designed for a wide range of DC-DC
conversion topologies, including step-up, SEPIC, and
flyback applications. They are for applications where
extremely low cost and small size are top priorities.
These devices are designed specifically to provide a
simple application circuit and minimize the size and
number of external components, making them ideal for
PDAs, digital cameras, and other low-cost consumer
electronics applications.
These devices use a unique fixed on-time, minimum off-
time architecture, which provides excellent efficiency
over a wide-range of input/output voltage combinations
and load currents. The fixed on-time is pin selectable to
either 0.5µs (50% max duty cycle) or 3µs (85% max
duty cycle), permitting optimization of external compo-
nent size and ease of design for a wide range of output
voltages.
The MAX1522/MAX1523 operate from a +2.5V to +5.5V
input voltage range and are capable of generating a
wide range of outputs. The MAX1524 is intended for
bootstrapped operation, permitting startup with lower
input voltage. All devices have internal soft-start and
short-circuit protection to prevent excessive switching
current during startup and under output fault condi-
tions. The MAX1522/MAX1524 have a latched fault
mode, which shuts down the controller when a short-
circuit event occurs, whereas the MAX1523 reenters
soft-start mode during output fault conditions. The
MAX1522/MAX1523/MAX1524 are available in a space-
saving 6-pin SOT23 package.
________________________Applications
____________________________Features
♦ Simple, Flexible Application Circuit
♦ 2-Cell NiMH or Alkaline Operation (MAX1524)
♦ Low Quiescent Current (25µA typ)
♦ Output Fault Protection and Soft-Start
♦ High Efficiency Over 1000:1 I OUT Range
♦ Pin-Selectable Maximum Duty Factor
♦ Micropower Shutdown Mode
♦ Small 6-Pin SOT23 Package
♦ No Current-Sense Resistor
MAX1522/MAX1523/MAX1524
Simple SOT23 Boost Controllers
________________________________________________________________ Maxim Integrated Products 1
__________Typical Operating Circuit
19-1926; Rev 0; 2/01
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
EVALUATION KIT
AVAILABLE
PART TEMP. RANGE
PIN-
PACKAGE TOP
MARK
MAX1522 EUT-T -40 ° C to +85 ° C 6 SOT23-6 AAOX
MAX1523 EUT-T -40
°
C to +85
°
C 6 SOT23-6 AAOY
MAX1524 EUT-T -40
°
C to +85
°
C 6 SOT23-6 AAOZ
Ordering Information
Pin Configurations
FB
SHDN SET
1 6 V CC
5 EXT
GND
MAX1522
MAX1523
MAX1524
SOT23-6
TOP VIEW
2
3 4
MAX1522
MAX1523
MAX1524
INPUT
OFF ON
6
3
4
5
2
1
V CC
EXT
SET FB
SHDN GND
OUTPUT
V
CC
50% 85%
N
Low-Cost, High-Current,
or High-Voltage Boost
Conversion
LCD Bias Supplies
Industrial +24V and +28V
Power Supplies
Low-Cost, Multi-Output
Flyback Converters
SEPIC Converters
Low-Cost Battery-
Powered Applications