STMicroelectronics L79L06ACUTR

Overview

L79L06ACUTR from STMicroelectronics is a three-terminal fixed negative voltage regulator delivering −6 V output at up to 100 mA, featuring internal current limiting, thermal overload protection, and short-circuit protection. It requires no external components and is rated for operation from −40 °C to +125 °C, making it suitable for local on-card regulation in industrial power supplies and embedded control systems.

For engineers reviewing the L79L06ACUTR datasheet, L79L06ACUTR pinout, L79L06ACUTR application, or L79L06ACUTR equivalent, key selection criteria include output voltage tolerance (±5%), dropout voltage (1.7 V), quiescent current (6 mA at 25 °C), and SO-8 package thermal performance with internally commingled heat-sink pins.

Technical Context

The L79L06ACUTR implements a monolithic bipolar linear regulator architecture with built-in thermal shutdown and foldback current limiting. Its output voltage is trimmed during manufacturing to −6.0 V ±5% at 25 °C, with load regulation of ≤30 mV over 1–40 mA and line regulation of ≤100 mV across input voltages from −9 V to −20 V.

It operates as a low-noise, fixed-output negative regulator with 50 µV RMS output noise (10 Hz–100 kHz) and 39–46 dB supply voltage rejection at 120 Hz. The device uses an internally commingled SO-8 package where pins 2, 3, 6, and 7 connect directly to the die attach flag for enhanced thermal dissipation.

Key Specifications

Pinout & Package

The L79L06ACUTR is housed in an SO-8 package with internal thermal enhancement: pins 2, 3, 6, and 7 are electrically connected to the die attach flag to reduce junction-to-case thermal resistance to 20 °C/W. External dimensions match standard SO-8, enabling drop-in compatibility with existing footprints.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar negative voltage regulation applications.

Compared with LM7906CDT and MC79L06CP, the L79L06ACUTR uniquely balances SO-8 footprint efficiency, 100 mA capability, and integrated thermal management-making it optimal for dense industrial PCBs where board area and thermal reliability are co-constrained.

Availability

L79L06ACUTR is available at Aetrix Electronics and suitable for industrial sensor interfaces, embedded microcontroller I/O power rails, and test equipment reference stages requiring stable component supply across multi-year production cycles.

Supply support for L79L06ACUTR 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 L79L00 series belongs to ST's legacy linear regulator product line, engineered specifically for cost-sensitive, space-constrained applications requiring robust fixed negative voltage regulation without external components.

FAQ

What is the minimum input voltage required for the L79L06ACUTR to maintain regulation?

The L79L06ACUTR requires a minimum input voltage of −7.7 V to sustain −6 V output under full 100 mA load, based on its 1.7 V dropout specification. At lighter loads (e.g., 40 mA), regulation holds down to −7.5 V. Input below −7.7 V causes output to track input minus dropout, resulting in unregulated behavior.

Can the L79L06ACUTR be used in parallel to increase output current?

No-parallel operation is not recommended. The L79L06ACUTR lacks current-sharing features such as matching output impedance or external current-sense inputs. Uneven thermal distribution and minor output voltage mismatches would cause one device to dominate conduction, risking thermal runaway and premature failure.

Is an input capacitor required for stable operation?

An input capacitor is not strictly required per datasheet test conditions, but a 0.33 µF ceramic capacitor placed close to Pin 2 (VIN) is strongly recommended to suppress high-frequency noise and prevent oscillation when sourced from long traces or switching supplies. This improves transient response and reduces EMI susceptibility.

How does the SO-8 thermal flag configuration affect PCB layout?

Pins 2, 3, 6, and 7 must be soldered to a single, uninterrupted copper pour of ≥6 cm² to achieve the rated 100 mA output. Splitting this thermal pad across multiple small polygons or using thermal relief spokes degrades R_thj-amb and risks thermal shutdown under sustained load. A solid internal layer connection is preferred over surface-only pours.