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MAX20343
Ultra-Low Quiescent Current,
Low Noise 3.5W Buck-Boost Regulator
General Description
Benefits and Features
● Extend System Run Time
The MAX20343 is an ultra-low quiescent current, non-
inverting buck-boost converter with 1A current capability
at 3.5V intended for applications that require long run
times while also demanding bursts of high current. The
device employs a unique control algorithm which seam-
lessly transitions between buck, buck-boost, and boost
modes, minimizing discontinuities and subharmonics in
the output voltage ripple. The low 1.9V input voltage for
startup allows users to power the device from a variety of
sources, and the near-zero minimum operating voltage
gives the user the ability to extract as much as possible
from their energy source. The MAX20343 has also been
designed to keep inductance and output capacitance
requirements as low as possible for space-constrained
applications.
• Ultra-Low, 3.5µA (typ) Quiescent Current
• 250mW Output Power with 500mV Input Voltage
• Dynamic Voltage Scaling (DVS)
● Low, Continuous Noise Profile
• Eliminates Discontinuities Across Operating
Voltage Range
• Eliminates Post-Filtering LDO in Noise Sensitive
Applications
● Adaptable Load Transient Response
• Adjustable Peak Current for Optimal Performance
in Each Application
• Fast Load Transient Response Minimizes Settling
Time
• Optional Feedback Integrator
The MAX20343 is ideal for power in optical sensor appli-
cations as well as for powering radios in low power, wide
area network (LPWAN) applications since in both cases
noise must be minimal and efficiency must be high. For
instance, the small light-load output voltage ripple allows
a photoplethysmography (PPG) system to operate at low
LED currents without interference. Additionally, seamless
transitions between operating modes enables the use of
dynamic voltage scaling (DVS) to minimize headroom on
the LED and to save power in such systems. In applica-
tions where a low-power-density battery must be buff-
ered by a super-capacitor to provide large LPWAN type
bursts of current, the ultra-low operating voltage of the
MAX20343 allows the user to extract as much energy
as possible from the super capacitor. The low output
inductance/capacitance requirement allows a small total
solution size. For example in PPG systems, this provides
the flexibility to place the MAX20343 on a remote optical
module if overcrowding on the main PCB is an issue.
• Enable for up to 3.5W Output Power Capabilities
• Disable for up to 3.2W Output Power and Faster
Load Transient Settling Time
• FAST Pin Pretriggers Load Response and Offers
Improved Load Transient
● Flexible Control Options
2
• I C Interface with Status Interrupts
• EN and Status Pins, Single-Resistor V
Selection (RSEL)
OUT
• See Table 3 for specific device defaults
● Extended Operating Temperature from -40°C
to +85°C
● Optimally Sized for Small Applications
• 16-bump, 1.77mm x 2.01mm, 0.4mm Pitch WLP
12-pin, 2.50mm x 2.50mm, Side-Wettable, 0.5mm
Pitch Flip-Chip QFN
• Inductor/Capacitor Available in 0603/0402 Case
Sizes
The MAX20343 is available with a highly configurable
I C serial interface or as a single-pin-enabled fixed-
Applications
2
● Biometric Optical Sensing Including PPG
● LPWAN (LTE/NB-IoT, LTE/Cat-M1)
● IoT
programming version. See Table 3 for specific device
settings. The device operates over the -40°C to +85°C
temperature range, is available in a 16-bump, 1.77mm x
2.01mm, 0.4mm pitch WLP package and a 12-pin, 2.50mm
x 2.50mm, 0.5mm pitch FC2QFN package.
● Industrial Sensors
Ordering Information appears at end of data sheet.
19-100516; Rev 4; 1/20