n Regulated Output with Input Voltages Above,
Below or Equal to the Output
n 2.4V to 7V VIN and 1.8V to 7V VOUT Ranges
n 5V VOUT at 500mA from 4 AA Cells
n Single Inductor
n Synchronous Rectification: Up to 94% Efficiency
n Burst Mode® Operation with 25µA IQ
n Output Disconnect in Shutdown
n 1MHz Switching Frequency
n <1µA Shutdown Current
n Small Thermally Enhanced 16-Lead (5mm × 3mm ×
0.75mm) DFN and 16-Lead GN Packages
n Medical Instruments
n Portable Barcode Readers
n Portable Inventory Terminals
n USB to 5V Supply
n Handheld GPS
7V, 500mA Synchronous
The LTC®3534 is a wide VIN range, highly efficient, fixed
frequency, buck-boost DC/DC converter that operates
from input voltages above, below or equal to the output
voltage. The topology incorporated in the IC provides a
continuous transfer function through all operating modes,
making the product ideal for multi-cell Alkaline/NiMH or
single Lithium-Ion/Polymer applications where the output
voltage is within the battery voltage range.
The LTC3534 offers extended VIN and VOUT ranges of 2.4V
to 7V and 1.8V to 7V, respectively. Quiescent current is
only 25µA in Burst Mode operation, maximizing battery
life in portable applications. Burst Mode operation is user
controlled and can be enabled by driving the PWM pin
low. If the PWM pin is driven high then fixed frequency
switching is enabled.
Other features include fixed 1MHz operating frequency, a
<1µA shutdown, short-circuit protection, programmable
soft-start, current limit and thermal overload protection.
The LTC3534 is available in the thermally enhanced 16-lead
(3mm × 5mm) DFN and 16-lead GN packages.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
Burst Mode is a registered trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
4 AA Cells to 5V at 500mA Buck-Boost Converter
3.6V TO 6.4V 4 AA +
PGND1 GND PGND2 330pF
4 AA Cells to 5V Efficiency vs VIN
PWM IOUT = 300mA
PWM IOUT = 500mA
3.6 4.0 4.4 4.8 5.2 5.6 6.0 6.4
For more information www.linear.com/LTC3534