STMicroelectronics L78L24ABD13TR

Overview

L78L24ABD13TR from STMicroelectronics is a three-terminal positive linear voltage regulator delivering a fixed 24 V output at up to 100 mA, featuring internal current limiting, thermal overload protection, and short-circuit protection. It requires no external components and operates across an input voltage range of 27–38 V, with 1.7 V dropout, making it suitable for local on-card regulation in industrial control modules and embedded power rails.

For engineers reviewing the L78L24ABD13TR datasheet, L78L24ABD13TR pinout, L78L24ABD13TR application, or L78L24ABD13TR equivalent, key selection criteria include ±4% output voltage tolerance (AB grade), -40°C to +125°C operating junction temperature, low 6.5 mA quiescent current at 25°C, and 31–37 dB supply voltage rejection at 120 Hz - all critical for noise-sensitive analog subsystems and long-life industrial deployments.

Technical Context

The L78L24ABD13TR implements a monolithic silicon-based linear regulation architecture with built-in foldback current limiting and thermal shutdown circuitry, ensuring robust fault handling without external supervision. Its internal bandgap reference and error amplifier maintain stable 24 V output under load variations from 1 mA to 100 mA and input transients within absolute maximum ratings.

Designed for fixed-voltage local regulation, it replaces discrete Zener/resistor networks with lower quiescent current (6.5 mA typ.), reduced output noise (200 µV RMS, 10 Hz–100 kHz), and tighter initial accuracy (±4% over temperature) - enabling cleaner biasing for op-amps, sensors, and microcontroller peripherals in space-constrained PCB layouts.

Key Specifications

Pinout & Package

Supplied in the SOT-89-3 surface-mount package, the L78L24ABD13TR features a thermally enhanced leadframe with pin 2 (GND) internally connected to the exposed die attach pad for improved heat dissipation. The compact 4.5 mm × 2.5 mm footprint supports high-density routing on cost-sensitive PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM78L24ACZ/NOPB and MC78L24CP, the L78L24ABD13TR provides superior thermal resilience (-40°C to +125°C), tighter ±4% output accuracy, lower quiescent current (6.5 mA vs. ≥8 mA), and SOT-89 packaging for better power dissipation - making it the optimal choice for new industrial and automotive designs demanding long-term reliability.

Availability

L78L24ABD13TR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, medical diagnostic sensors, and smart building HVAC controllers requiring stable component supply with full traceability and lifecycle continuity.

Supply support for L78L24ABD13TR 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, MCU, power, and sensing solutions for industrial, automotive, and consumer markets.

The L78L series belongs to ST's legacy linear regulator product line, engineered specifically for cost-effective, robust local voltage regulation in space-constrained and thermally demanding applications - emphasizing simplicity, reliability, and wide operating temperature compliance.

FAQ

What is the minimum input voltage required for regulation at full 100 mA load?

The L78L24ABD13TR maintains regulation down to 25.7 V input (24 V + 1.7 V dropout) at 40 mA per datasheet test conditions. At 100 mA, thermal derating applies: with adequate PCB copper heatsinking (≥1 cm²), regulation holds to ~26.5 V input. Below that, output sags proportionally - verify via thermal simulation for your specific layout.

Can this regulator be used in parallel to increase output current?

No. The L78L24ABD13TR lacks current-sharing capability and has no parallel operation guidance in its datasheet. Attempting parallel connection risks thermal runaway due to mismatched output voltages and unbalanced current distribution. For >100 mA, use a single higher-current regulator (e.g., L7824CD2T) or add an external pass transistor with proper biasing.

Is the SOT-89-3 package RoHS-compliant and lead-free?

Yes. The L78L24ABD13TR carries the "D13TR" suffix indicating STMicroelectronics' standard RoHS-compliant, lead-free SOT-89-3 package per EU Directive 2011/65/EU, with matte tin (Sn) termination and halogen-free molding compound - verified in ST's official material declaration (DocID2145 Rev 25, Section 7.6).

How does the 200 µV output noise impact precision ADC references?

At 200 µV RMS (10 Hz–100 kHz), the L78L24ABD13TR contributes <0.00083% error to a 24 V full-scale ADC reference - negligible for 12-bit systems (LSB = 5.86 mV), but may limit effective resolution in 16-bit+ designs. For ultra-high-precision applications, add a low-noise post-regulator (e.g., REF5025) or RC filter (10 Ω + 10 µF) to reduce noise by ~20 dB.