L79M05T-TL-E Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The L79M05T-TL-E is a linear voltage regulator IC manufactured by onsemi, designed to provide a fixed negative 5V output at 500mA. This through-hole component operates across a temperature range of -30°C to 80°C and features integrated over-current and over-temperature protection. The part is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations.

Substiute Parts

L79M05T-TL-E

onsemiIn Stock: 2084L79M05T-TL-E Datasheet

Current PartRFQ

LM120H-5.0/NOPB

Texas InstrumentsIn Stock: 1715LM120H-5.0/NOPB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the L79M05T-TL-E is determined by the following critical parameters:

• Output voltage specification: -5V fixed negative output
• Output current capability: minimum 500mA required
• Negative voltage regulation topology
• Through-hole mounting configuration
• Protection features: over-current and over-temperature capability
• Operating temperature range compatibility
• Regulatory compliance (REACH, ECCN classification)

The LM120H-5.0/NOPB from Texas Instruments qualifies as a functional substitute based on matching output voltage (-5V), exceeding output current capability (1.5A vs. 500mA), maintaining negative output configuration, and providing through-hole mounting in a compatible package. Both components share identical regulatory classification (EAR99, REACH Unaffected) and HTSUS coding.

Parameter Comparison

Engineering Selection Recommendations

The LM120H-5.0/NOPB is the primary substitute for the obsolete L79M05T-TL-E. Selection is supported by the following factors:

• Active product status ensures ongoing availability and manufacturing support
• Output current specification of 1.5A exceeds the original 500mA requirement, providing design margin
• Identical fixed -5V output voltage maintains circuit compatibility
• Extended operating temperature range (-55°C to 150°C) encompasses the original specification
• Improved PSRR (64dB vs. 50dB at 120Hz) provides superior noise rejection
• Identical regulatory classification (EAR99, REACH Unaffected) and HTSUS coding
• RoHS3 compliance status provides additional environmental qualification

Package differences exist: the original uses TO-251-3 Short Leads (IPak), while the substitute uses TO-39-3 Metal Can. Physical layout and thermal management characteristics differ accordingly. PCB footprint redesign is required for implementation.

Frequently Asked Questions (FAQ)

Q: Can the LM120H-5.0/NOPB directly replace the L79M05T-TL-E without circuit modification?

A: Electrical functionality is compatible. Both components provide fixed -5V output with negative voltage regulation topology. However, package differences (TO-251-3 vs. TO-39-3) require PCB footprint redesign. Thermal management characteristics differ due to package geometry.

Q: What is the significance of the higher current rating (1.5A vs. 500mA) in the substitute?

A: The LM120H-5.0/NOPB output current specification of 1.5A exceeds the original 500mA requirement. This provides design margin and allows the substitute to support higher load currents if circuit requirements increase. The component will not force higher current through the circuit; it simply permits it.

Q: Are there package compatibility considerations?

A: Yes. The L79M05T-TL-E uses TO-251-3 Short Leads (IPak) packaging, while the LM120H-5.0/NOPB uses TO-39-3 Metal Can (TO-205AD) packaging. These are physically distinct packages requiring different PCB footprints and mounting approaches. Thermal dissipation characteristics also differ.

Q: How do the operating temperature ranges compare?

A: The original L79M05T-TL-E operates from -30°C to 80°C. The LM120H-5.0/NOPB operates from -55°C to 150°C, providing a wider temperature envelope. If the application operates within the original -30°C to 80°C range, the substitute remains fully qualified.

Q: What protection features are provided by each component?

A: The L79M05T-TL-E includes over-current and over-temperature protection. The LM120H-5.0/NOPB provides over-temperature protection. Both components include thermal shutdown capability. Over-current protection differences should be evaluated against specific circuit requirements.

Q: Are regulatory and compliance certifications equivalent?

A: Both components share identical ECCN classification (EAR99), REACH status (REACH Unaffected), HTSUS coding (8542.39.0001), and Moisture Sensitivity Level (MSL 1 - Unlimited). The substitute adds RoHS3 compliance certification. Regulatory equivalence is established.