ADI LT3645EMSE#PBF

The LT3645 is a dual output regulator combining a 500mA buck regulator and a 200mA low dropout linear regulator (LDO). The wide input voltage range of 3.6 to 36 makes the LT3645 suitable for regulating power from a wide variety of sources, including 24V industrial supplies and automotive batteries. Its high operating frequency allows the use of tiny, low cost inductors and capacitors, resulting in a very small solution.

Cycle-by-cycle current limit and frequency foldback provide protection against shorted outputs. Soft-start and frequency foldback eliminate input current surge during start-up.

The linear regulator operates from the VCC2 pin at voltages down to 1.2V. It supplies 200mA of output current with a typical dropout voltage of 310mV.

Other features of the LT3645 include a <2μA shutdown, short circuit protection, soft-start and thermal shutdown. The LT3645 is available in the thermally enhanced 16-lead (3mm×3mm) QFN package, or a 12-lead MSE package.

• Wide Input Range: Operation from 3.60 to 36V
• Overvoltage Lockout Protects Circuit Through 55V Transients on Input
• 500mA Output Current Switching Regulator
• High Switching Frequency: 750kHz
• 200mA Low Dropout Linear Regulator 1.21 to 16V Input; 0.8V to dV Output
• 310mV Dropout Voltage VCC2 to OUT2
• Precision Programmable Undervoltage Lockout
• Short-Circuit Robust
• Internal Soft-Start
• <2μA Shutdown Current
• Small Thermally Enhanced 16-Lead (3mm×3mm) QFN and 12-Lead MSE Packages

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