STMicroelectronics L79L06ABUTR

Overview

L79L06ABUTR 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 specified for operation across -40 °C to +125 °C junction temperature, making it suitable for local on-card regulation in industrial control and embedded power subsystems.

For engineers reviewing the L79L06ABUTR datasheet, L79L06ABUTR pinout, L79L06ABUTR application, or L79L06ABUTR equivalent, key selection criteria include its ±4% output voltage tolerance at 25 °C, 1.7 V dropout voltage, 50 µV RMS output noise (10 Hz–100 kHz), 39–46 dB supply voltage rejection at 120 Hz, and SO-8 package with internally connected thermal flag pins (2, 3, 6, 7).

Technical Context

This device implements a monolithic bipolar linear regulator architecture with built-in thermal shutdown and foldback current limiting. Its internal structure eliminates need for external compensation or bypass capacitors beyond standard input/output decoupling (CI = 0.33 µF, CO = 0.1 µF).

Designed for fixed negative rail generation, it operates with input voltages down to -8.5 V (for -6 V output) and up to -20 V, maintaining load regulation of ≤30 mV over 1–40 mA and line regulation of ≤100 mV across its rated input range.

Key Specifications

Pinout & Package

Package: SO-8 with modified internal frame - pins 2, 3, 6, and 7 electrically connected to the die attach flag for enhanced thermal dissipation (R_thj-case = 20 °C/W). Requires ≥6 cm² PCB copper area for heatsinking per datasheet thermal data.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar negative linear regulator applications.

Compared with LM7906CDT and MC79L06ACDR2G, L79L06ABUTR offers the best balance of industrial temperature range (-40 °C to +125 °C), SO-8 thermal performance (R_thj-case = 20 °C/W), and ±4% output accuracy - ideal for high-reliability embedded systems needing regulated negative rails without external pass devices.

Availability

L79L06ABUTR is available at Aetrix Electronics and suitable for industrial sensor nodes, legacy serial interface modules, and embedded analog front-ends requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for L79L06ABUTR 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 consumer markets since 1987.

L79L06ABUTR belongs to the L79L00 series of three-terminal negative linear regulators, engineered specifically for robust local regulation in space- and reliability-constrained embedded systems where simplicity, thermal resilience, and wide temperature operation are critical.

FAQ

What is the minimum input voltage required for L79L06ABUTR to maintain regulation?

The minimum input voltage is -7.7 V DC, calculated as V_OUT − V_DROP = -6 V − 1.7 V. Below this, output voltage drops linearly with input; the device remains functional but exits regulation. This value assumes full 100 mA load and 25 °C ambient - derate for higher temperature or current.

Can L79L06ABUTR be used in parallel to increase output current?

No - the L79L06ABUTR lacks current-sharing features and has no built-in balancing mechanism. Parallel connection risks thermal runaway due to mismatched dropout voltages and thermal coefficients. For higher current, use an external pass transistor configured per ST's AN1057 application note.

Is an input capacitor mandatory for stable operation?

Yes - a minimum 0.33 µF ceramic capacitor at the VIN pin is required per the datasheet test circuits and stability analysis. Omitting it risks oscillation under transient load conditions, especially with long input traces or high-impedance sources. The capacitor must be placed within 5 mm of pins 1 and 2.

Does the SO-8 thermal flag require a dedicated PCB thermal pad or can it connect to ground?

Pins 2, 3, 6, and 7 are internally connected to the die attach flag and must be soldered to a ≥6 cm² copper area acting as a heatsink - not necessarily tied to circuit ground. Electrical isolation from GND is permissible; thermal conduction is the primary requirement. Use thermal vias to inner-layer copper planes for optimal performance.