STMicroelectronics

L78L33ABD  

Linear & Switching Voltage Regulators

L78L33ABD Description

The L78L33ABD from STMicroelectronics is a fixed-output 3.3V linear voltage regulator designed for low-power applications. This surface-mount (SO-8 package) device delivers a stable 100mA output current with an input voltage range up to 30V, making it suitable for a variety of electronic systems. It features over-current, over-temperature, and short-circuit protection, ensuring robust operation in demanding environments. With a quiescent current of 5.5mA and a PSRR of 49dB at 120Hz, it provides efficient noise suppression, ideal for sensitive analog and digital circuits. Although marked as obsolete, its ROHS3 compliance and REACH-unaffected status make it a viable choice for legacy designs.

L78L33ABD Features

• Fixed 3.3V Output: Precision-regulated voltage for stable power delivery.
• Wide Input Range (Up to 30V): Accommodates varying input sources.
• Low Quiescent Current (5.5mA): Enhances efficiency in battery-operated devices.
• High PSRR (49dB at 120Hz): Superior noise rejection for clean power supply.
• Protection Mechanisms: Over-current, over-temperature, and short-circuit safeguards.
• Surface-Mount (SO-8) Package: Compact footprint for space-constrained PCBs.
• RoHS3 Compliant & REACH Unaffected: Meets environmental standards.

L78L33ABD Applications

The L78L33ABD excels in low-power, noise-sensitive applications, including:

• Embedded Systems: Powering microcontrollers, sensors, and peripherals.
• Consumer Electronics: Voltage regulation in portable devices, audio equipment, and IoT modules.
• Industrial Controls: Reliable power management for PLCs and instrumentation.
• Automotive Electronics: Auxiliary power supply for infotainment or low-power subsystems.
• Legacy Designs: Suitable for maintaining or upgrading older systems requiring 3.3V regulation.

Conclusion of L78L33ABD

The L78L33ABD is a dependable, compact linear regulator offering stable 3.3V output, robust protection, and low noise performance. While obsolete, its wide input range, high PSRR, and compliance with environmental standards make it a practical choice for legacy or low-power designs. Ideal for embedded, consumer, and industrial applications, it balances performance with reliability in voltage-sensitive circuits. Engineers should evaluate alternative modern equivalents for new designs but can leverage this regulator for proven, low-risk solutions.

L78L33ABD Documents

Download datasheets and manufacturer documentation for L78L33ABD

Datasheets :

L78L Datasheet