ON Semiconductor's NCV891x34 are dual-mode regulators intended for automotive, battery-connected applications that must operate with up to a 45 V input supply. Hybrid low power mode allows the NCV891x34 to operate either as a PWM Buck Converter or as a low dropout linear regulator, and the NCV891x34 is suitable for systems with low noise and low quiescent current requirements often encountered in automotive driver information systems. A reset (with fixed delay) and a fault pin (flagging low input voltage and high temperature warnings) simplify interfacing with a microcontroller. Two pins are provided to synchronize switching to a clock, or to another NCV891x34. The NCV891x34 also provides several protection features expected in automotive power supply systems such as current limit, short circuit protection, and thermal shutdown. In addition, the high switching frequency produces low output voltage ripple even when using small inductor values and an all-ceramic output filter capacitor forming a space-efficient switching regulator solution.