STMicroelectronics L7805ACD2T-TR

Overview

L7805ACD2T-TR from STMicroelectronics is a three-terminal positive fixed-voltage linear regulator delivering 5 V ±2 % output at up to 1.5 A, featuring thermal overload protection, short-circuit protection, and safe operating area (SOA) protection. It operates across 0 to 125 °C junction temperature and supports local on-card regulation in power supplies for microcontrollers, sensors, and industrial control modules.

For engineers reviewing the L7805ACD2T-TR datasheet, L7805ACD2T-TR pinout, L7805ACD2T-TR application, or L7805ACD2T-TR equivalent, key selection criteria include guaranteed 2 % output tolerance over temperature, 2 V dropout voltage at 1 A, 68 dB supply voltage rejection at 120 Hz, 10 µV/√Hz output noise, and D²PAK package thermal resistance of 3 °C/W junction-to-case.

Technical Context

This IC implements a monolithic series-pass linear regulation architecture with internal current limiting, thermal shutdown, and SOA protection-enabling robust operation without external protection circuitry. Its fixed 5 V output is trimmed during manufacturing to ±2 % accuracy at 25 °C and maintains stability under load currents from 5 mA to 1.5 A.

Designed for DC input voltages from 7.5 V to 18 V (with absolute max 35 V), it delivers regulated output with line regulation as tight as 2 mV (typ.) over 8–12 V input range and load regulation of 30 mV (max) across 5 mA–1.5 A. Junction temperature monitoring and thermal foldback ensure reliability in sustained high-power dissipation scenarios.

Key Specifications

Pinout & Package

The L7805ACD2T-TR is housed in a surface-mount D²PAK (TO-263) package with three terminals: Input (Pin 1), Ground (Pin 2), and Output (Pin 3). This thermally enhanced package provides low junction-to-case resistance for high-current linear regulation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM7805CD2T and MC7805BD2TG, the L7805ACD2T-TR offers tighter initial tolerance, guaranteed performance across 0–125 °C, lower quiescent current, and superior ripple rejection-making it optimal for industrial and automotive applications demanding long-term stability and fault resilience.

Availability

L7805ACD2T-TR is available at Aetrix Electronics and suitable for industrial PLCs, automotive ECUs, medical monitoring devices, and point-of-sale terminals requiring stable component supply and long-lifecycle support.

Supply support for L7805ACD2T-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 silicon solutions for automotive, industrial, and power management applications.

The L78 series belongs to ST's legacy positive voltage regulator IC product line, engineered for rugged, cost-effective local regulation in harsh environments-prioritizing built-in protection, wide temperature operation, and mechanical robustness over programmability or ultra-low IQ.

FAQ

What is the minimum input voltage required for regulation?

The L7805ACD2T-TR requires a minimum input voltage of 7.5 V to maintain 5 V output at full 1.5 A load, based on its 2 V dropout specification. Below this, output voltage collapses linearly with input; datasheet testing confirms stable regulation down to 7.3 V at reduced load (5–1 A) and 25 °C.

Can this regulator drive a 1.5 A load continuously in a D²PAK package?

Yes-provided adequate PCB copper area (≥4 cm² 2-oz copper thermal pad) and ambient temperature ≤50 °C. With R_thJC = 3 °C/W and R_thCA ≈ 25 °C/W, total thermal resistance is ~28 °C/W; at 1.5 A and 2 V dropout (3 W dissipation), junction rise is ~84 °C, keeping T_J < 125 °C.

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

Yes-mandatory for stability. ST specifies ≥0.33 µF ceramic at input (Pin 1) and ≥0.1 µF ceramic at output (Pin 3), placed as close as possible to the device. Larger values (e.g., 10 µF tantalum + 100 nF ceramic) improve transient response but do not replace the minimum ceramic requirement.

How does its short-circuit protection behave under sustained fault conditions?

Under sustained short-circuit, the device limits steady-state output current to ~0.2 A while activating thermal shutdown if junction temperature exceeds ~165 °C. After cooling below ~140 °C, it auto-restarts-cycling on/off until fault is removed. Peak short-circuit current reaches 2.2 A briefly during fault initiation.