MAX8572

Features:

 15V or Adjustable Output Voltage Up to 28V
 Safety Features Protect Against Output Faults
 20mA at 20V from a Single Li+ Battery
 True Shutdown
 87% Efficiency
 Up to 800kHz Switching Frequency
 Small 6-Pin SOT23 Package


Application

LCD Bias Generators
Polymer LEDs (OLED)
Cellular or Cordless Phones
Palmtop Computers
Personal Digital Assistants (PDAs)
Organizers
Handy Terminals


Pinout




Specifications

V_CC, ,SHDN to GND..................................................   -0.3V to +6V
SW to GND.................................................  -0.3V to (V_CC + 0.3V)
FB to GND (MAX8570/MAX8571/
MAX8574)...............................................     -0.3V to (V_CC + 0.3V)
OUT to GND (MAX8572/MAX8573/MAX8575) .......  - 0.3V to +30V
L_X to GND ..............................................................-0.3V to +30V
I_LX, I_CC .............................................................................600mA
Continuous Power Dissipation (T_A = +70°C)
SOT23-6 (derate 8.7 mW/°C above +70°C)............. 695.7 mW
Operating Temperature Range ........................-40°C to +85°C
Junction Temperature.....................................................+150°C
Storage Temperature Range .........................-65°C to +150°C
Lead Temperature (soldering, 10s) ...............................+300°C


Description

The MAX8570 family of LCD step-up converters uses an internal n-channel switch and an internal p-channel output isolation switch. These converters operate from a 2.7V to 5.5V supply voltage and deliver up to 28V at the output.

A unique control scheme provides the highest efficiency over a wide range of load conditions. The internal  MOSFET switch reduces external component count and a high switching frequency (up to 800kHz) allows for tiny surface-mount components. Three current-limit options are available. The MAX8570 and MAX8572 use a 110mA current limit to reduce ripple and component size in low-current applications. For high-power requirements, the MAX8574 and MAX8575 use a 500mA current limit and supply up to 20mA at 20V. The MAX8571 and MAX8573 use a 250mA current limit for a compromise between ripple and power. Built-in safety features protect the internal switch and down-stream components from fault conditions.

Additional features include a low quiescent current and a True Shutdown™ mode to save power. The MAX8570/MAX8571/MAX8574 allow the user to set the output voltage between 3V and 28V, and the MAX8572/MAX8573/MAX8575 have a preset 15V output. These step-up converters are ideal for small LCD panels with low current requirements, but can also be used in other applications. The MAX8571 evaluation kit is available to help reduce design time.