Circuit Intégré LT1170 Monolithic High Power Switching Regulator

Description

CIRCUIT INTEGRE LT1170 MONOLITHIC HIGH POWER SWITCHING REGULATOR

100kHz, 5A, 2.5A and 1.25A High Efficiency Switching Regulators

FEATURES
Wide Input Voltage Range: 3V to 60V
– Low Quiescent Current: 6mA
– Internal 5A Switch (2.5A for LT1171,
1.25A for LT1172)
– Shutdown Mode Draws Only 50mA Supply Current
– Very Few External Parts Required
– Self-Protected Against Overloads
– Operates in Nearly All Switching Topologies
– Flyback-Regulated Mode Has Fully Floating Outputs
– Comes in Standard 5-Pin Packages
– LT1172 Available in 8-Pin MiniDIP and Surface Mount
Packages
– Can Be Externally Synchronized

APPLICATIONS
Logic Supply 5V at 10A
– 5V Logic to ±15V Op Amp Supply
– Battery Upconverter
– Power Inverter (+ to –) or (– to +)
– Fully Floating Multiple Outputs
DESCRIPTION
The LT®1170/LT1171/LT1172 are monolithic high power
switching regulators. They can be operated in all standard
switching configurations including buck, boost, flyback,
forward, inverting and “Cuk.” A high current, high efficiency
switch is included on the die along with all oscillator,
control and protection circuitry. Integration of all
functions allows the LT1170/LT1171/LT1172 to be built in
a standard 5-pin TO-3 or TO-220 power package as well as
the 8-pin packages (LT1172). This makes them extremely
easy to use and provides “bust proof” operation similar to
that obtained with 3-pin linear regulators.
The LT1170/LT1171/LT1172 operate with supply voltages
from 3V to 60V, and draw only 6mA quiescent
current. They can deliver load power up to 100W with no
external power devices. By utilizing current-mode switching
techniques, they provide excellent AC and DC load and
line regulation.
The LT1170/LT1171/LT1172 have many unique features
not found even on the vastly more difficult to use low
power control chips presently available. They use adaptive
antisat switch drive to allow very wide ranging load currents
with no loss in efficiency. An externally activated
shutdown mode reduces total supply current to 50mA
typically for standby operation.