STMicroelectronics L7808ABD2T

Overview

L7808ABD2T from STMicroelectronics is a three-terminal positive linear voltage regulator delivering a fixed 8 V output with up to 1.5 A continuous current, thermal overload and short-circuit protection, and ±2 % output voltage tolerance over -40 °C to +125 °C operating junction temperature - used for local regulation in industrial power supplies and embedded control modules.

For engineers reviewing the L7808ABD2T datasheet, L7808ABD2T pinout, L7808ABD2T application, or L7808ABD2T equivalent, this page provides verified electrical specs, TO-220FP package details, thermal resistance data (R_thJC = 5 °C/W), load/line regulation limits, and real-world substitution guidance for legacy 8 V supply designs.

Technical Context

The L7808ABD2T implements a monolithic series pass transistor architecture with internal current limiting, safe operating area (SOA) protection, and thermal shutdown circuitry - enabling robust operation without external protection components. Its design targets fixed-voltage local regulation where input-to-output differential voltage remains ≥2 V.

It operates across an input voltage range of 10.6 V to 25 V for stable 8 V output at 1 A, with line regulation ≤80 mV and load regulation ≤100 mV under specified conditions. The device requires minimum 5 mA load current for regulation and uses standard 0.33 µF input / 0.1 µF output ceramic capacitors per test circuits.

Key Specifications

Pinout & Package

Package: TO-220FP (3-lead, full-pack plastic, isolated tab, vertical mounting).

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 and MC7808ACT, the L7808ABD2T uniquely combines ±2 % tolerance, -40 °C to +125 °C operation, and integrated SOA protection - making it the sole choice for industrial and automotive applications demanding guaranteed performance across full temperature extremes.

Availability

L7808ABD2T is available at Aetrix Electronics and suitable for industrial PLCs, automotive body control units, legacy instrumentation, and test equipment requiring stable component supply with long-term lifecycle visibility.

Supply support for L7808ABD2T 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, specializing in power management, microcontrollers, and analog ICs for industrial, automotive, and consumer markets.

The L78 series was designed specifically for cost-effective, robust local voltage regulation in space-constrained embedded systems - emphasizing thermal resilience, protection integration, and wide-input compatibility without external components.

FAQ

What is the minimum input voltage required for regulation with L7808ABD2T?

The minimum input voltage is 10.6 V under typical conditions (IO = 5 mA to 1 A, TJ = 25 °C), based on its 2 V dropout specification. At full 1 A load and elevated temperature, VI must exceed 10 V + worst-case dropout (up to ~2.2 V) to maintain regulation - confirmed in Table 5 of DS0422 Rev 38.

Can L7808ABD2T be used without a heatsink?

Yes, for low-power operation: at 500 mA load and ambient ≤40 °C, junction temperature stays below 125 °C with R_thJA = 60 °C/W (TO-220FP). Above 700 mA or in enclosed enclosures, a heatsink is required - thermal calculations must use actual R_thJC = 5 °C/W and board copper area.

Does L7808ABD2T require input and output capacitors?

Yes: STMicroelectronics specifies 0.33 µF ceramic at input and 0.1 µF ceramic at output (per Figure 4 and test conditions). These stabilize loop response and prevent oscillation; omitting them risks instability or poor transient performance - especially with long input traces or high-ESR capacitors.

How does L7808ABD2T handle short-circuit conditions?

It limits steady-state short-circuit current to 0.2 A (I_SC) while maintaining thermal shutdown activation at ~165 °C junction temperature. Peak short-circuit current reaches 2.2 A briefly before foldback - protecting both the IC and upstream supply, as validated in absolute maximum ratings and electrical characteristics tables.