General Description
The MAX8633–MAX8636 offer low-dropout (LDO) volt-
age and ultra-low-power regulation in a subminiaturized
2mm x 2mm µDFN package. The devices operate from
a 2.7V to 5.5V supply and deliver up to 300mA from
each output, with a typical dropout voltage of 90mV at
100mA load current. Each device is designed with
internal p-channel MOSFET pass transistors to ensure a
low-quiescent supply current of 54µA (typical, both
LDOs on). Other features include low-noise operation
(MAX8634/MAX8636), output current limiting, and ther-
mal shutdown.
The MAX8633 features an open-drain, active-low
RESET output to monitor OUT2, eliminating external
components and adjustments. The MAX8633 asserts a
RESET signal (120ms minimum timeout) when VOUT2
drops below 87% of the nominal output voltage. The
MAX8634/MAX8636 feature a noise bypass input to the
internal reference for low output noise (45µV
RMS
typ).
The MAX8634/MAX8635 provide independent SHDN
inputs for disabling the regulators, while the MAX8633/
MAX8636 provide a single SHDN input for disabling
both regulators.
The MAX8633/MAX8635/MAX8636 have two logic
inputs that select one of nine preset output-voltage
combinations, eliminating external 1% resistors, as well
as inventory burden. The MAX8634 has one logic input
to select three output-voltage options.
The MAX8633–MAX8636 are available in an 8-pin, 2mm
x 2mm µDFN package for minimizing footprint, and an
8-pin, 3mm x 3mm TDFN package for higher power dis-
sipation. The devices are specified over the extended
temperature range (-40°C to +85°C). All packages are
lead free.
Applications
Cellular and Cordless Phones
PDAs and Digital Cameras
Small LCD Displays
Notebook Computers
Wireless LAN Cards
Handheld Instruments
Features
♦ Pin-Programmable Output Voltages
♦ 300mA Output Current
♦ Low 90mV Dropout at 100mA Load
♦ Open-Drain, Active-Low RESET (MAX8633)
♦ Low 45µV
RMS
Output Noise (MAX8634/MAX8636)
♦ Low 54µA Quiescent Supply Current
♦ Low < 1µA Maximum Shutdown Current
♦ Output Current Limit
♦ Thermal Shutdown
MAX8633–MAX8636
Dual 300mA Pin-Programmable LDO
Linear Regulators
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
Typical Operating Circuits
19-0516; Rev 1; 9/08
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.
+
Denotes a lead-free/RoHS-compliant package.
Ordering Information continued at end of data sheet.
Pin Configurations and Selector Guide appear at end of
data sheet.
EVALUATION KIT
AVAILABLE