General Description
The MAX38640–MAX38643 are a nanoPower family of
ultra-low 330nA quiescent current buck (step-down) DCDC
converters that operate from 1.8V to 5.5V input voltage
and support load currents of up to 175mA, 350mA,
700mA with peak efficiencies of 96%. While in shutdown,
there is only 5nA of shutdown current. The devices offer
ultra-low quiescent current, small total solution size, and
high efficiency throughout the load range. The
MAX38640–MAX38643 are ideal for battery applications
where long battery life is a must.
The MAX38640–MAX38643 family utilizes a unique control
scheme that allows ultra-low quiescent current and
high efficiency over a wide output current range. The
MAX38642 excludes active discharge resistor in shutdown,
which allows the output to be regulated or held high
by another source or by the charged output capacitor.
The MAX38640–MAX38643 devices are offered in a
space-saving 1.42mm x 0.89mm, 6-pin WLP (2x3 bump,
0.4mm pitch), as well as a 2mm x 2mm, 6-pin μDFN package.
All parts are specified over the -40°C to +85°C extended
temperature range.

Benefits and Features
● Extends Battery Life
• 330nA Ultra-Low Quiescent Supply Current
• 5nA Shutdown Current
• 96% Peak Efficiency and over 88% at 10μA
● Easy to Use – Addresses Popular Operation
• 1.8V to 5.5V Input Range
• Single Resistor-Adjustable VOUT from 0.7V to 3.3V
(A-Option)
• Preprogrammed VOUT from 0.5V to 5.0V (B-Option)
• ±1.75% Output Voltage Accuracy
• Up to 175mA/350mA/700mA Load Current
● Protects System in Multiple Use Cases
• Reverse-Current Blocking in Shutdown
• Optional Active Discharge Feature
● Reduces Size and Increases Reliability
• -40°C to +85°C Temperature Range
• 2mm x 2mm, 6-pin μDFN Package
• 1.42mm x 0.89mm, 0.4mm Pitch 6-pin (2 x 3) WLP

Applications
● Portable, Space-Constrained Consumer Products
● Wearable Devices, Ultra-Low-Power IoT, NB IoT, and
Bluetooth® LE
● Single Li-ion (Li+) and Coin Cell Battery Products
● Wired or Wireless Industrial Products