STMicroelectronics L7808ABV-DG

Overview

L7808ABV-DG from STMicroelectronics is a three-terminal positive fixed-voltage linear regulator delivering 8 V at up to 1.5 A output current, featuring thermal overload protection, short-circuit protection, and SOA protection. It operates across –40 °C to +125 °C junction temperature range and maintains ±2 % output voltage tolerance, making it suitable for industrial power rails, embedded microcontroller supply domains, and automotive body-control modules requiring stable local regulation.

For engineers reviewing the L7808ABV-DG datasheet, L7808ABV-DG pinout, L7808ABV-DG application, or L7808ABV-DG equivalent, key selection criteria include guaranteed extended-temperature operation (–40 to +125 °C), dropout voltage of 2 V at 1 A, load regulation ≤100 mV over 5 mA–1.5 A, and 62 dB supply voltage rejection at 120 Hz - all critical for noise-sensitive analog subsystems and thermally constrained PCB layouts.

Technical Context

This IC implements a monolithic series-pass linear regulator architecture with internal current limiting, thermal shutdown, and safe operating area (SOA) protection. Its design eliminates need for external compensation and supports local on-card regulation without remote sensing.

It requires only two external capacitors (0.33 µF input, 0.1 µF output) for stability and delivers regulated 8 V output with line regulation as tight as 5 mV (typ.) over 11–17 V input range at 25 °C - enabling robust performance in unregulated 12 V or 24 V intermediate bus applications.

Key Specifications

Pinout & Package

Supplied in TO-220FP package (3-pin, vertical mounting, isolated tab), with pin 1 = Input, pin 2 = Ground, pin 3 = Output. The isolated tab allows direct mechanical mounting to heatsink without electrical isolation hardware.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output linear regulator applications.

Compared with LM340T-8.0/NOPB and MC7808ACT, L7808ABV-DG provides superior thermal robustness (–40 °C start-up), tighter regulation, and isolated TO-220FP packaging - directly enabling simplified thermal management and broader environmental deployment without derating.

Availability

L7808ABV-DG is available at Aetrix Electronics and suitable for industrial automation controllers, automotive body electronics, medical diagnostic devices, and test equipment requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for L7808ABV-DG includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets.

L7808ABV-DG belongs to the L78 positive voltage regulator IC family, engineered for rugged, cost-effective local regulation in space-constrained systems where reliability across wide temperature ranges is mandatory.

FAQ

What is the minimum input voltage required for stable 8 V output at 1 A load?

The datasheet specifies VI ≥ 10.6 V for full-load operation (IO = 1 A) across the entire temperature range. At 25 °C, dropout is 2 V, so 10 V suffices - but 10.6 V ensures margin for worst-case thermal and line conditions per Table 5. Input below this risks regulation loss and increased output ripple.

Can L7808ABV-DG be used without a heatsink?

Yes, for loads ≤500 mA at ambient ≤50 °C with free-air convection, due to its 60 °C/W junction-to-ambient thermal resistance (TO-220FP). Above that, junction temperature exceeds 125 °C without heatsinking. Thermal calculation must include power dissipation (VI − 8 V) × IO and ambient conditions.

Does this device require input and output capacitors, and what values are recommended?

Yes: a minimum 0.33 µF ceramic capacitor at the input and 0.1 µF ceramic capacitor at the output are mandatory for stability per Figure 4 and Table 10–16. Larger values (e.g., 10 µF tantalum + 100 nF ceramic in parallel) improve transient response and ripple suppression but are not required for basic regulation.

How does the L7808ABV-DG handle short-circuit conditions?

It limits output current to ~200 mA (Isc) continuously during steady-state short, while tolerating up to 2.2 A (Iscp) peak during fault initiation. Internal thermal shutdown activates if junction temperature exceeds ~165 °C, and the device automatically recovers once cooled - no latch-up or manual reset required.