STMicroelectronics L7808ABV

Overview

L7808ABV from STMicroelectronics is a three-terminal positive fixed-voltage linear regulator delivering 8 V at up to 1.5 A output current, with ±2 % output voltage tolerance and guaranteed operation from –40 °C to +125 °C. It integrates thermal overload protection, short-circuit protection, and safe operating area (SOA) protection, and is commonly used for local on-card regulation in industrial power supplies and embedded control modules.

For engineers reviewing the L7808ABV datasheet, L7808ABV pinout, L7808ABV application, or L7808ABV equivalent, key selection criteria include its extended temperature range (–40 to +125 °C), 2 V dropout voltage at 1 A, 62 dB supply voltage rejection at 120 Hz, 18 mΩ output resistance, and compatibility with standard TO-220FP mounting and heat sinking.

Technical Context

The L7808ABV implements a monolithic series-pass linear regulation architecture with internal current limiting and thermal shutdown circuitry. Its feedback loop maintains stable 8 V output across input voltages from 10.6 V to 25 V and load currents from 5 mA to 1.5 A.

Designed for fixed-output use without external components, it supports adjustable configurations via external resistors and capacitors. The device operates with minimum 5 mA load current and requires input-to-output differential ≥2 V for regulation under full load.

Key Specifications

Pinout & Package

Package: TO-220FP (Full Pack), 3-pin vertical mount with isolated tab, compatible with standard heatsinks and PCB through-hole assembly.

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 MC7808BD2TR4G, the L7808ABV offers tighter output tolerance (±2 %), guaranteed operation down to –40 °C, lower quiescent current, and superior thermal performance in TO-220FP - making it optimal for mission-critical industrial and automotive applications demanding reliability across full environmental range.

Availability

L7808ABV is available at Aetrix Electronics and suitable for industrial PLC power rails, automotive body control modules, medical diagnostic instrumentation, and point-of-sale terminal logic supplies requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for L7808ABV 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 analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The L78 series belongs to ST's legacy positive voltage regulator IC product line, engineered for robust local regulation in harsh environments where simplicity, reliability, and thermal resilience outweigh efficiency optimization.

FAQ

What is the minimum input voltage required for regulation at full 1.5 A load?

The L7808ABV requires a minimum input voltage of 10.6 V at 25 °C to maintain 8 V output under 1 A load, and ≥12.6 V to sustain regulation at 1.5 A with margin. At –40 °C, derating applies due to increased dropout; consult Figure 11 in DS0422 Rev 38 for full VI–IO–TJ curves.

Can L7808ABV be used in parallel to increase output current?

No - the L7808ABV lacks built-in current-sharing features such as output offset trimming or master-slave control. Parallel connection risks thermal runaway due to mismatched dropout voltages and is not recommended. For >1.5 A, use a single higher-current regulator or switch-mode solution.

Is an input bypass capacitor mandatory, and what value is recommended?

Yes - a minimum 0.33 µF ceramic capacitor placed ≤10 mm from the input pin is mandatory for stability and transient immunity. ST recommends adding a 10–100 µF electrolytic capacitor in parallel for bulk energy storage when input impedance is high or source inductance exceeds 1 µH.

Does L7808ABV require a heatsink in TO-220FP package at 1 A continuous load?

Yes - at 1 A and 25 °C ambient, junction temperature rise is ~60 °C (R_thJA = 60 °C/W × (2 V × 1 A) = 60 °C). With 125 °C max T_J, this leaves only 40 °C margin. A heatsink reducing R_thJA to ≤40 °C/W is strongly advised for continuous 1 A operation in enclosed or elevated ambient conditions.