The LT3641 is a dual channel, current mode monolithic buck switching regulator with a power-on reset and a watchdog timer. Both regulators are synchronized to a single oscillator with an adjustable frequency (350kHz to 2.5MHz). At light loads, both regulators operate in low ripple Burst Mode®to maintain high effi ciency and low output ripple.The high voltage channel is a nonsynchronous buck with an internal 2.4A top switch that operates from an input of 4V to 42V and input transient protection to 55V. The low voltage channel operates from an input of 2.5V to 5.5V. Internal synchronous power switches provide high effi ciency without the need of external Schottky diode. Both channels have cycle-by-cycle current limit, providing protection against shorted outputs.The power-on reset and watchdog timeout periods are both adjustable using external capacitors. The window mode watchdog timer fl ags when the μP pulses group too close together or too far apart.The LT3641 is available in a 28-pin 4mm × 5mm QFN package and 28-pin TSSOP package. Both packages have an exposed pad for low thermal resistance.ApplicationsIndustrial Power SuppliesAutomotive Electronic Control Units