LT1432-3.3_1081659

VIN Pin .................................................................... 30V
V+ Pin ..................................................................... 40V
VC ........................................................................... 35V
VLIM and VOUT Pins ................................................... 7V
Diode Pin Voltage ................................................... 30V
Mode Pin Current (Note 2) ..................................... 1mA
Operating Temperature Range .................... 0°C to 70°C
Storage Temperature Range ................ 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C


Description

The LT®1432-3.3 is a control chip designed to operate with the LT1171/LT1271 family of switching regulators to make a very high efficiency 3.3V step-down (buck) switching regulator. A minimum of external components is needed. Included is an accurate current limit which uses only 60mV sense voltage and uses "free" PC board trace material for the sense resistor. Logic controlled electronic shutdown mode draws only 15mA battery current. The switching regulator operates down to 4.5V input.
 The LT1432-3.3 has a logic controlled Burst Mode operation to achieve high efficiency at very light load currents (0mA to 100mA) such as memory keep-alive. In normal switching mode, the standby power loss is about 30mW, limiting efficiency at light loads. In Burst Mode operation, standby loss is reduced to approximately 11mW. Output current in this mode is typically in the 5mA to 100mA range.
 The LT1432-3.3 is available in 8-pin SO and PDIP packages. The LT1171/LT1271 is also available in surface mount DD packages.