STMicroelectronics L7808ABD2T-TR

Overview

L7808ABD2T-TR from STMicroelectronics is a three-terminal positive linear voltage regulator delivering a fixed 8 V output with up to 1.5 A continuous current, ±2 % output voltage tolerance (A grade), thermal overload and short-circuit protection, and operation across –40 °C to +125 °C junction temperature. It serves as a local on-card power supply in industrial control modules requiring stable low-noise DC bias for microcontrollers and analog sensors.

For engineers reviewing the L7808ABD2T-TR datasheet, L7808ABD2T-TR pinout, L7808ABD2T-TR application, or L7808ABD2T-TR equivalent, key selection criteria include dropout voltage (2 V at 1 A), load regulation (≤30 mV over 5 mA–1.5 A), supply voltage rejection (62 dB at 120 Hz), junction-to-ambient thermal resistance (62.5 °C/W in D²PAK), and guaranteed extended-temperature performance.

Technical Context

This device implements a monolithic series-pass linear regulator architecture with internal current limiting, safe operating area (SOA) protection, and thermal shutdown circuitry. Its fixed-output design eliminates external feedback components while supporting adjustable configurations via external resistors and capacitors.

It operates with input voltages up to 35 V (for 8 V output), requires minimum 5 mA load current for regulation, and uses standard 0.33 µF input and 0.1 µF output ceramic capacitors per test circuits in DS0422. Output noise is specified at 10 µV/√Hz (10 Hz–100 kHz).

Key Specifications

Pinout & Package

The L7808ABD2T-TR is housed in a surface-mount D²PAK (TO-263) package with three terminals: Input (IN), Ground (GND), and Output (OUT). This thermally enhanced package supports higher power dissipation than DPAK or TO-220FP variants when mounted on PCB copper planes.

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 MC7808CD2TG, the L7808ABD2T-TR provides superior thermal robustness (–40 °C to +125 °C), tighter output accuracy (±2 %), and integrated SOA protection-making it the preferred choice for safety-critical or thermally demanding embedded power rails.

Availability

L7808ABD2T-TR is available at Aetrix Electronics and suitable for industrial automation controllers, automotive body electronics, medical infusion devices, and test equipment requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for L7808ABD2T-TR 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 microcontrollers, power management ICs, sensors, and analog chips for industrial, automotive, and consumer markets.

The L78 series belongs to ST's legacy positive voltage regulator product line, engineered for rugged, cost-effective local DC-DC conversion in space-constrained and thermally challenging environments-prioritizing reliability, protection integration, and broad operating temperature coverage.

FAQ

What is the minimum input voltage required for stable 8 V output at 1.5 A?

The L7808ABD2T-TR requires a minimum input voltage of 10.6 V under nominal conditions (IO = 5 mA to 1 A, VI = 10.6–21 V), rising to ≥12 V at full 1.5 A load due to 2 V dropout. For reliable operation across temperature, maintain ≥13 V input to accommodate worst-case dropout and line regulation drift.

Can this regulator be used without an input capacitor?

No. The datasheet mandates a minimum 0.33 µF ceramic capacitor placed within 10 mm of the IN pin to prevent oscillation and ensure stability under transient load changes. Omitting it risks high-frequency instability, output overshoot, and potential damage during input voltage surges.

How does the thermal shutdown behave during sustained overload?

When junction temperature exceeds ~165 °C, the internal thermal limiter disables the pass transistor, dropping output voltage to near zero. Once the die cools by ~15 °C, automatic recovery occurs. This hiccup-mode behavior protects against permanent damage but requires adequate PCB copper area or heatsinking to avoid repeated cycling in continuous overload.

Is the L7808ABD2T-TR RoHS-compliant and halogen-free?

Yes. Per STMicroelectronics' official documentation (DS0422 Rev 38), the L7808ABD2T-TR is manufactured in full compliance with RoHS Directive 2011/65/EU and is halogen-free per IEC 61249-2-21, with lead-free terminations and green molding compound.