Linear Technology/Analog Devices' LT8603 is a quad (4) output that combines two (2) high input, step-down switching regulators, one (1) low input step-down regulator, and a boost controller. With the boost controller configured to supply the chip V_IN supply, the LT8603 produces three precisely regulated outputs even when the boost input voltage falls significantly below the regulated output voltages, such as during an automotive cold crank scenario. Alternatively, with the boost controller driven from one of the step-down regulator outputs or configured as a SEPIC, the LT8603 provides four precisely regulated outputs over a wide input voltage range. The LT8603 provides robust regulation by including a cycle-by-cycle current limit for all step-down regulators, thermal shutdown, and a boost controller that can tolerate reverse battery connections and negative transient input voltages down to -42 V. The LT8603 is ideal for automotive stop-start/cold crank ride through, industrial controls, and power supply applications.