L9788

The L9788 is a high-efficiency, step-down DC-DC converter designed by STMicroelectronics for power management in portable and embedded systems. It operates with an input voltage range from 3.0 V to 5.5 V, making it suitable for applications powered by single-cell Li-ion batteries or standard 5 V supplies. The device delivers up to 2 A of continuous output current, ensuring reliable performance under varying load conditions. This regulator features a synchronous rectification topology, which significantly improves efficiency—typically exceeding 90%—even at light loads. Its integrated high-side and low-side MOSFETs reduce external component count, simplify design, and enhance thermal performance. The L9788 supports adjustable output voltage via an external resistor divider, allowing flexibility in system power architecture. Designed for stability and fast transient response, the L9788 employs a constant-frequency PWM control scheme with peak current-mode regulation. This ensures minimal output ripple and quick adaptation to sudden changes in load current, critical for sensitive analog circuits and microcontrollers. The internal soft-start function prevents inrush current during startup, protecting both the IC and the system. The L9788 includes comprehensive protection features such as over-current protection (OCP), over-temperature shutdown (OTP), and undervoltage lockout (UVLO). These safeguards enhance reliability in harsh environments or unexpected operating conditions. Additionally, the device supports enable functionality, allowing external control of the power-on sequence for optimized system power management. Packaged in a compact 3 mm × 3 mm WDFN-8 package, the L9788 offers excellent thermal performance and easy integration into space-constrained designs. It is ideal for use in wearable electronics, IoT devices, smart sensors, and battery-powered medical equipment where efficiency, small size, and robustness are essential. With its low quiescent current and high switching frequency (up to 2 MHz), the L9788 minimizes the size of external passive components while maintaining stable operation across a wide range of applications. Its compatibility with ceramic capacitors further simplifies PCB layout and reduces overall solution cost.