The L4931CD33 from STMicroelectronics is a fixed-output linear voltage regulator designed to deliver a stable 3.3V output with a maximum current of 250mA. This surface-mount IC operates with an input voltage range up to 20V, making it suitable for a variety of power supply applications. With a low dropout voltage of 0.8V at 250mA, it ensures efficient performance even when the input voltage is close to the output level. The device features over-current and over-temperature protection, enhancing reliability in demanding environments. Although marked as obsolete, it remains a robust choice for legacy designs due to its low quiescent current (1mA) and high PSRR (73dB to 55dB), which minimizes noise in sensitive circuits.
The L4931CD33 is ideal for applications requiring stable, low-noise power:
The L4931CD33 offers a balance of efficiency, reliability, and noise suppression, making it a versatile solution for low-power voltage regulation. While obsolete, its high PSRR, low dropout, and protection features ensure continued relevance in legacy and niche applications. Engineers seeking a cost-effective, stable 3.3V regulator with robust performance will find this IC a practical option, particularly in noise-sensitive or space-constrained designs.
Download datasheets and manufacturer documentation for L4931CD33