General Description
The MIC2171 is a complete 100 kHz SMPS
current-mode controller with an internal 65V 2.5A
power switch.
Although primarily intended for voltage step-up
applications, the floating switch architecture of the
MIC2171 makes it practical for step-down, inverting,
and Cuk configurations, as well as isolated topologies.
Operating from 3V to 40V, the MIC2171 draws only
7 mA of quiescent current, making it attractive for
battery-operated applications.
The MIC2171 is available in a 5-pin TO-220 or TO-263
package that allows –40°C to +85°C ambient
temperature operation.
Features
• 2.5A, 65V Internal Switch Rating
• 3V to 40V Input Voltage Range
• Current Mode Operation, 2.5A Peak
• Internal Cycle-by-Cycle Current Limit
• Twice the Frequency of the LM2577
• Low External Electronic Components Count
• Suitable for Most Switching Topologies
• 7 mA Quiescent Current (Operating)
• Fits LT1171/LM2577 TO-220 and TO-263 Sockets

Applications
• Laptop/Palmtop Computers
• Battery Operated Equipment
• Handheld Instruments
• Off-Line Converter up to 50W (Requires External
Power Switch)
• Predriver for Higher Power Capability