STMicroelectronics

LF33ABDT

LF33ABDT Description

The LF33ABDT from STMicroelectronics is a fixed-output linear voltage regulator designed to deliver a stable 3.3V output with a maximum current capacity of 500mA. Housed in a DPAK (TO-252) package, this surface-mount device is optimized for applications requiring reliable voltage regulation with low dropout (0.7V @ 500mA) and high efficiency. With an input voltage range up to 16V, it ensures robust performance in diverse power supply scenarios. The regulator features overcurrent and overtemperature protection, enhancing system reliability under fault conditions. Although marked as obsolete, it remains a viable choice for legacy designs due to its proven performance and compliance with ROHS3 and REACH standards.

LF33ABDT Features

• Fixed 3.3V Output: Precision-regulated voltage for stable power delivery.
• Low Dropout Voltage: 0.7V at full load (500mA), minimizing power dissipation.
• High PSRR (80dB @ 120Hz): Superior noise rejection for sensitive analog/digital circuits.
• Low Quiescent Current (1mA): Enhances efficiency in battery-operated systems.
• Protection Mechanisms: Overcurrent and overtemperature safeguards.
• Wide Input Range (Up to 16V): Compatible with various power sources.
• DPAK Package: Compact, surface-mount design for space-constrained PCBs.
• Compliance: ROHS3, REACH unaffected, and ECCN EAR99 certified.

LF33ABDT Applications

The LF33ABDT is ideal for:

• Embedded Systems: Powering microcontrollers, sensors, and low-power ICs.
• Consumer Electronics: Voltage regulation in set-top boxes, routers, and audio devices.
• Industrial Controls: Reliable supply for PLCs, motor drivers, and instrumentation.
• Automotive Electronics: Auxiliary power in infotainment or telematics (non-critical).
• Legacy Designs: Cost-effective replacement or maintenance for obsolete systems.

Conclusion of LF33ABDT

The LF33ABDT offers a balance of performance, efficiency, and protection, making it suitable for low-to-medium power applications. Its high PSRR and low dropout are standout features for noise-sensitive designs, while the DPAK package ensures easy integration. Although discontinued, its robust specifications and compliance with environmental standards sustain its relevance in legacy and cost-sensitive projects. Engineers seeking a dependable 3.3V regulator with proven reliability may find this device a practical solution.