FEATURES
n Wide Input Voltage Range: 2.9V to 40V
n Positive or Negative Output Voltage Programming
with a Single Feedback Pin
n Current Mode Control Provides Excellent Transient
Response
n Programmable Operating Frequency (100kHz to
1MHz) with One External Resistor
n Synchronizable to an External Clock
n Low Shutdown Current < 1µA
n Internal 7.2V Low Dropout Voltage Regulator
n Programmable Input Undervoltage Lockout with
Hysteresis
n Programmable Soft-Start
n Small 10-Lead DFN (3mm × 3mm) and Thermally
Enhanced 10-Pin MSOP Packages
n AEC-Q100 Qualified for Automotive Applications

APPLICATIONS
n Automotive and Industrial Boost, Flyback, SEPIC and
Inverting Converters
n Telecom Power Supplies
n Portable Electronic Equipment

DESCRIPTION
The LT®3757/LT3757A are wide input range, current
mode, DC/DC controllers which are capable of generating
either positive or negative output voltages. They can be
configured as either a boost, flyback, SEPIC or inverting
converter. The LT3757/LT3757A drive a low side external
N-channel power MOSFET from an internal regulated 7.2V
supply. The fixed frequency, current-mode architecture
results in stable operation over a wide range of supply
and output voltages.
The operating frequency of LT3757/LT3757A can be set
with an external resistor over a 100kHz to 1MHz range,
and can be synchronized to an external clock using the
SYNC pin. A low minimum operating supply voltage of
2.9V, and a low shutdown quiescent current of less than
1µA, make the LT3757/LT3757A ideally suited for batteryoperated systems.
The LT3757/LT3757A feature soft-start and frequency
foldback functions to limit inductor current during startup and output short-circuit. The LT3757A has improved
load transient performance compared to the LT3757.