KA79M12 Equivalent & Substitute Parts

Part Overview

The KA79M12 is a linear voltage regulator IC manufactured by onsemi, designed to provide a fixed negative 12V output at 500mA in a TO-220-3 package. This device is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The KA79M12 serves applications requiring negative voltage regulation with thermal and short-circuit protection in through-hole mounting configurations.

Substiute Parts

KA79M12

onsemiIn Stock: 7385KA79M12 Datasheet

Current PartRFQ

MC7912ACTG

onsemiIn Stock: 2296MC7912ACTG Datasheet

SimilarRFQ

MC7912BTG

onsemiIn Stock: 15364MC7912BTG Datasheet

SimilarRFQ

MC7912CTG

onsemiIn Stock: 5003MC7912CTG Datasheet

SimilarRFQ

MC79M12BTG

onsemiIn Stock: 3820MC79M12BTG Datasheet

SimilarRFQ

L7912ACV

STMicroelectronicsIn Stock: 25408L7912ACV Datasheet

SimilarRFQ

L7912ACV-DG

STMicroelectronicsIn Stock: 5502L7912ACV-DG Datasheet

SimilarRFQ

L7912CV

STMicroelectronicsIn Stock: 75321L7912CV Datasheet

SimilarRFQ

L7912CV-DG

STMicroelectronicsIn Stock: 158950L7912CV-DG Datasheet

SimilarRFQ

LM79M15CT

National SemiconductorIn Stock: 4834LM79M15CT Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the KA79M12 is determined by the following critical parameters:

• Output voltage: -12V fixed
• Output current capability: minimum 500mA
• Package type: TO-220-3 (through-hole)
• Input voltage rating: -35V maximum
• Protection features: Over temperature and short circuit protection
• Mounting configuration: Through hole

Substitute parts are grouped into two categories:

Direct Current Rating Equivalents (500mA): Parts with identical 500mA output current rating and matching electrical specifications.

Higher Current Capacity Substitutes (1A and 1.5A): Parts with increased output current capability that maintain all other critical parameters, providing design flexibility for applications with potential current margin requirements.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation - Direct Equivalent: MC79M12BTG (onsemi) is the closest functional equivalent to the KA79M12. It maintains identical 500mA output current, -12V fixed output voltage, and TO-220-3 package configuration. The part is active status with extended operating temperature range (-40°C to 125°C) and includes over-current protection in addition to over-temperature protection. RoHS3 compliance provides regulatory advantage over the obsolete KA79M12.

Secondary Recommendation - Same Manufacturer, Higher Current: MC7912BTG or MC7912CTG (onsemi) provide 1A output current capability while maintaining all other critical parameters. These parts are active status with RoHS3 compliance. Selection between BTG (extended temperature -40°C to 125°C) and CTG (standard temperature 0°C to 125°C) depends on application temperature requirements.

Alternative Manufacturer - Higher Current Capacity: L7912CV or L7912CV-DG (STMicroelectronics) deliver 1.5A output current with active product status. These parts maintain the same -12V output, TO-220-3 package, and operating temperature range as the KA79M12. RoHS3 compliance and over-temperature/short-circuit protection align with original specifications.

Parametric Equivalent: LM79M15CT (National Semiconductor) matches the KA79M12 in 500mA output current and electrical characteristics. This part is active status with identical operating temperature range and protection features. However, RoHS compliance status is non-compliant, which may restrict use in regulated applications.

Frequently Asked Questions (FAQ)

Q: Can MC79M12BTG directly replace KA79M12 in existing designs? A: Yes. MC79M12BTG is a direct functional equivalent with identical 500mA output current, -12V fixed output, and TO-220-3 package. The extended operating temperature range (-40°C to 125°C) provides additional margin. No circuit modifications are required.

Q: What is the advantage of using MC7912BTG or L7912CV instead of MC79M12BTG? A: These parts provide higher output current capability (1A for MC7912 series, 1.5A for L7912 series) while maintaining all other specifications. This allows designs to operate with greater current margin or support future load increases without component substitution.

Q: Are all substitute parts available in the same TO-220-3 package? A: Yes. All listed substitute parts use TO-220-3 through-hole packaging, ensuring mechanical and thermal compatibility with existing PCB layouts and heatsink configurations.

Q: What is the difference between MC7912ACTG, MC7912BTG, and MC7912CTG? A: All three parts are 1A output regulators from onsemi with identical electrical specifications. The primary difference is operating temperature range: ACTG (0°C to 125°C), BTG (-40°C to 125°C extended range), and CTG (0°C to 125°C). Selection depends on application temperature requirements.

Q: Why is LM79M15CT listed as a parametric equivalent rather than a direct substitute? A: LM79M15CT matches the KA79M12 in output current (500mA) and electrical performance. However, it carries RoHS non-compliant status, which may conflict with regulatory requirements in certain applications. It remains a valid technical equivalent for legacy or non-regulated designs.

Q: Can I use L7912ACV-DG if L7912CV-DG is unavailable? A: Both parts are functionally identical with 1.5A output current and -12V fixed output. L7912ACV-DG is obsolete status while L7912CV-DG is active. For new designs, L7912CV-DG is preferred. For legacy support, L7912ACV-DG remains available with existing inventory.

Q: What protection features should I verify when selecting a substitute? A: All listed substitutes include over-temperature protection. Verify that short-circuit or over-current protection is present in your selected part. MC79M12BTG and onsemi MC7912 series include over-current protection, while L7912 series include short-circuit protection. Both protection schemes are functionally equivalent for regulator safety.