CE9380/CE9381,pdf datasheet (S

The CE9380/1 is a CMOS step-up switching DC/DC converter that mainly consists of a reference voltage source, an oscillator, and a comparator. The ST9380 allows the duty ratio to be automatically switched according to the load (light load: 50%, high output current: 75%), enabling products with a low ripple over a wide range, high efficiency, and high output current. With the CE9380/1, a step-up switching DC/DC converter can be configured by using an external coil, capacitor, diode and NMOS or NPN. The built-in MOSFET is turned off by a protection circuit when the voltage at the LX pin exceeds the limit to prevent it from
being damaged. This feature, along with the mini package and low current consumption, makes the ST9380 ideal for applications such as the power supply unit of portable equipment.