STMicroelectronics

L7809ABD2T

L7809ABD2T Description

The L7809ABD2T is a fixed-output linear voltage regulator from STMicroelectronics, designed to deliver a stable 9V output at up to 1.5A of continuous current. Housed in a D2PAK (TO-263) surface-mount package, this regulator is optimized for applications requiring robust power management with minimal external components. With an input voltage range up to 35V and a typical dropout voltage of 2V @ 1A, it ensures reliable performance in demanding environments. The device features over-temperature and short-circuit protection, enhancing system durability. Though marked as obsolete, it remains a viable choice for legacy designs due to its proven reliability and compliance with ROHS3 and REACH standards.

L7809ABD2T Features

• High Current Capacity: Supports 1.5A output current, making it suitable for power-hungry applications.
• Low Dropout Voltage: 2V @ 1A (Typ) ensures efficient operation even with lower input voltages.
• Robust Protection: Integrated over-temperature and short-circuit protection safeguards against fault conditions.
• Excellent Ripple Rejection: 61dB PSRR (120Hz) minimizes noise, ideal for sensitive analog/digital circuits.
• Wide Input Range: Accepts up to 35V input, accommodating fluctuating power sources.
• Low Quiescent Current: 6 mA Iq reduces power waste in standby modes.
• Surface-Mount Design: D2PAK package offers superior thermal dissipation for high-power applications.

L7809ABD2T Applications

• Industrial Power Supplies: Stable voltage regulation for control systems, PLCs, and motor drivers.
• Automotive Electronics: Auxiliary power for infotainment, sensors, and lighting systems (within input limits).
• Consumer Electronics: Power management in audio amplifiers, set-top boxes, and legacy devices.
• Embedded Systems: Reliable voltage conversion for microcontrollers and peripheral circuits.
• Test & Measurement Equipment: Low-noise power delivery for precision instruments.

Conclusion of L7809ABD2T

The L7809ABD2T is a dependable linear regulator offering high current output, robust protection, and excellent noise suppression. While obsolete, its D2PAK package, wide input range, and thermal protection make it a strong candidate for legacy or cost-sensitive designs requiring a 9V rail. Engineers valuing simplicity, durability, and compliance may still find it advantageous in industrial, automotive, and consumer applications. For new designs, consider modern alternatives with lower dropout or higher efficiency, but the L7809ABD2T remains a proven solution for stable power delivery.