Features

• Input Voltage Range: 4V to 48V
• Adjustable Regulated Output: 2.4V to 12.5V
• Output Current: 50mA Maximum
• 16μA Quiescent Current in Regulation at No Load
• Input Fault Protection from –52V to 60V
• Multimode Charge Pump (2:1, 1:1) with Automatic Mode Switching Maintains Regulation Over Wide V_IN Range
• Input Voltage Shunt Mode for Current-Fed Applications
• Power Good Output
• Overtemperature and Short-Circuit Protection
• Operating Junction Temperature: 150°C Maximum
• Thermally Enhanced 10-Lead MSOP and 10-Lead (3mm × 3mm) DFN packages

Typical Application

Description

The LTC®3255 is a switched-capacitor step-down DC/DC converter that produces a regulated output (2.4V to 12.5V adjustable) from a 4V to 48V input. In applications where the input voltage exceeds twice the output voltage, 2:1 capacitive charge pumping extends output current capability beyond input supply current limits. At no load, Burst Mode® operation cuts V_IN quiescent current to 16μA.

With its integrated V_IN shunt regulator, the LTC3255 excels in 4mA to 20mA current loop applications. The device enables current multiplication; a 4mA input current can power a 7.4mA load continuously. Alternatively, the LTC3255 serves as a higher efficiency replacement for linear regulators and provides a space-saving inductorfree alternative to buck DC/DC converters.

The LTC3255 withstands reverse-polarity input supplies and output short-circuits without damage. Safety features including current limit and overtemperature protection further enhance robustness. The LTC3255 is available in thermally enhanced 10-lead MSOP and low profile 3mm × 3mm 10-lead DFN packages.