LT1936_15 Datasheet, PDF (1/20 Pages) Linear Technology – 1.4A, 500kHz Step-Down Switching Regulator

FEATURES
■ _{Wide Input Range: 3.6V to 36V}
■ _{Short-Circuit Protected Over Full Input Range}
■ _{1.9A Guaranteed Minimum Switch Current}
■ _{5V at 1.4A from 10V to 36V Input}
■ _{3.3V at 1.4A from 7V to 36V Input}
■ _{5V at 1.2A from 6.3V to 36V Input}
■ _{3.3V at 1.2A from 4.5V to 36V Input}
■ _{Output Adjustable Down to 1.20V}
■ _{500kHz Fixed Frequency Operation}
■ _Soft-Start
■ _{Uses Small Ceramic Capacitors}
■ _{Internal or External Compensation}
■ _{Low Shutdown Current: <2μA}
■ _{Thermally Enhanced 8-Lead MSOP Package}
APPLICATIONS
■ _{Automotive Battery Regulation}
■ _{Industrial Control Supplies}
■ _{Unregulated Wall Adapters}
LT1936
1.4A, 500kHz Step-Down
Switching Regulator
DESCRIPTION
The LT^®1936 is a current mode PWM step-down DC/DC
converter with an internal 1.9A power switch, packaged
in a tiny, thermally enhanced 8-lead MSOP. The wide in-
put range of 3.6V to 36V makes the LT1936 suitable for
regulating power from a wide variety of sources, including
automotive batteries, 24V industrial supplies and unregu-
lated wall adapters. Its high operating frequency allows the
use of small, low cost inductors and ceramic capacitors,
resulting in low, predictable output ripple.
Cycle-by-cycle current limit, frequency foldback and
thermal shutdown provide protection against shorted
outputs, and soft-start eliminates input current surge
during start-up. Transient response can be optimized by
using external compensation components, or board space
can be minimized by using internal compensation. The
low current (<2μA) shutdown mode enables easy power
management in battery-powered systems.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
TYPICAL APPLICATION
V_IN
4.5V TO 36V
ON OFF
3.3V Step-Down Converter
V_IN BOOST ^0.22μF
SHDN
SW
4.7μF
LT1936
COMP
FB
V_C GND
10k
10μH
17.4k
V_OUT
3.3V
1.2A
22μF
1936 TA01a
95
V_IN = 12V
90
Efficiency
V_OUT = 5V
85
V_OUT = 3.3V
80
75
70
65
0
0.5
1
LOAD CURRENT (A)
1.5
1936 TA01b
1936fd
1