FAN53555UC03X

The FAN53555UC03X from ON Semiconductor is a highly efficient, digitally programmable step-down (buck) switching voltage regulator. It is designed to deliver a continuous output current of up to 5A from an input voltage supply ranging from 2.5V to 5.5V. The output voltage is digitally programmable via an I2C interface, offering flexibility for various power rail requirements.

This regulator operates at a fixed switching frequency of 2.4MHz, which allows for the use of small external components, such as a 330nH output inductor and a 20µF output capacitor. It utilizes synchronous rectification for high efficiency, exceeding 80% even at low load currents. The device also features Pulse Frequency Modulation (PFM) for power-save mode at light loads, reducing quiescent current to a typical 60µA. For higher loads, it automatically switches to fixed-frequency control.

The FAN53555UC03X is housed in a compact 20-bump, 1.6 x 2 mm WLCSP (Wafer-Level Chip-Scale Package). This small footprint makes it suitable for space-constrained designs. The package is surface-mount compatible. Key features include internal soft-start, input under-voltage lockout (UVLO), and thermal shutdown and overload protection.

Applications for this regulator include processors for mobile phones, tablets, wearable electronics, digital cameras, and networking equipment, as well as low voltage, high current point-of-load applications. Its programmable output and high current capability make it a versatile solution for modern portable and battery-powered devices.