Texas Instruments UA79M05CKCSE3

Overview

UA79M05CKCSE3 from Texas Instruments is a fixed-negative-voltage linear regulator delivering −5 V output at up to 500 mA, featuring internal short-circuit limiting, thermal shutdown, and dropout voltage of 1.1 V at 5 mA. It operates across 0°C to 125°C and is used in on-card regulation for noise-sensitive analog subsystems and industrial power rails.

For engineers reviewing the UA79M05CKCSE3 datasheet, UA79M05CKCSE3 pinout, UA79M05CKCSE3 application, or UA79M05CKCSE3 equivalent, key selection criteria include guaranteed −5 V output tolerance (±50 mV over temperature), input voltage range (−7 V to −25 V), ripple rejection (≥54 dB at 120 Hz), and TO-220 (KC) package thermal resistance (θ_JA = 19°C/W).

Technical Context

This device implements a monolithic PNP pass transistor with safe-area compensation and current-limiting circuitry integrated on a single silicon die. Its architecture provides stable negative regulation without external components while maintaining immunity to overload via thermal shutdown and foldback current limiting.

It requires only 2-µF input and 1-µF output capacitors for stability, supports adjustable configurations using external resistors, and functions as a power-pass element in precision tracking regulators - all within a 3-terminal TO-220 (KC) package with common-emitter topology.

Key Specifications

Pinout & Package

UA79M05CKCSE3 is housed in a TO-220 (KC) package with 3 terminals: Input (collector), Output (emitter), and Common (base). The package features a metal tab electrically connected to the Common terminal and supports heatsink mounting for thermal management.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM7905CT and UA79M05CKVURG3, UA79M05CKCSE3 offers optimal thermal resistance in through-hole form factor, enabling robust 500 mA operation without forced airflow - ideal for field-deployed industrial controllers where mechanical reliability outweighs board-area savings.

Availability

UA79M05CKCSE3 is available at Aetrix Electronics and suitable for industrial sensor interfaces, legacy instrumentation upgrades, and embedded control system power rails requiring stable component supply and long-term obsolescence mitigation.

Supply support for UA79M05CKCSE3 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

Texas Instruments is a U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and power management ICs with global manufacturing and quality certification.

The UA79M05 series belongs to TI's legacy linear regulator product line, designed specifically for robust, no-frills negative-voltage regulation in industrial, automotive, and medical equipment where reliability and long-term availability are critical.

FAQ

What is the maximum input voltage rating for UA79M05CKCSE3?

The absolute maximum input voltage for UA79M05CKCSE3 is −35 V, but the recommended operating range is −7 V to −25 V. Exceeding −25 V may degrade ripple rejection and increase thermal stress. For reliable long-term operation, maintain input within this range and ensure adequate heatsinking at full load.

Does UA79M05CKCSE3 require external capacitors for stability?

Yes, UA79M05CKCSE3 requires a minimum 2-µF capacitor on the input and a 1-µF capacitor on the output to ensure stability and transient response. These values are specified in the datasheet and validated across temperature and load conditions. Ceramic or tantalum types are acceptable, but avoid low-ESR electrolytics without series resistance.

Is UA79M05CKCSE3 pin-compatible with older µA79M05 variants?

Yes, UA79M05CKCSE3 uses the same TO-220 (KC) package and identical pinout (Input–Common–Output) as legacy µA79M05 devices. Electrical specifications including output voltage tolerance, dropout, and thermal shutdown thresholds match the original design, enabling direct replacement in existing PCBs without modification.

What is the thermal resistance θ_JA of UA79M05CKCSE3 in its TO-220 package?

The junction-to-ambient thermal resistance (θ_JA) for UA79M05CKCSE3 in the TO-220 (KC) package is 19°C/W under JEDEC High-K board conditions. This value assumes proper heatsinking via the metal tab; actual performance depends on PCB copper area, airflow, and mounting hardware.

Can UA79M05CKCSE3 be used in adjustable configurations?

Yes, UA79M05CKCSE3 can be configured as an adjustable negative regulator by adding external resistors between Output and Common, and between Common and Adjust (using a separate reference IC or Zener diode). However, the device itself is fixed-output; adjustability requires additional components and alters regulation accuracy and noise performance.