MC7809ACTG Equivalent & Substitute Parts

Part Overview

The MC7809ACTG is a linear voltage regulator IC from onsemi, designed to provide a fixed 9V positive output at 1A current capacity 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 MC7809ACTG delivers regulated power management in applications requiring stable 9V rails with moderate current demands and thermal protection against overcurrent and temperature excursions.

Substiute Parts

MC7809ACTG

onsemiIn Stock: 1766MC7809ACTG Datasheet

Current PartRFQ

MC7809CTG

onsemiIn Stock: 23360MC7809CTG Datasheet

Parametric EquivalentRFQ

L7809ACV

STMicroelectronicsIn Stock: 2496L7809ACV Datasheet

DirectRFQ

L7809CV

STMicroelectronicsIn Stock: 204263L7809CV Datasheet

SimilarRFQ

L78M09CV

STMicroelectronicsIn Stock: 9997L78M09CV Datasheet

SimilarRFQ

L78S09CV

STMicroelectronicsIn Stock: 2712L78S09CV Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the MC7809ACTG is determined by the following critical parameters:

• Output Voltage: Must be fixed at 9V
• Package / Case: Must be TO-220-3 for mechanical and thermal compatibility
• Mounting Type: Must be Through Hole
• Output Configuration: Must be Positive
• Protection Features: Must include Over Temperature and Short Circuit protection
• RoHS Compliance: Must maintain ROHS3 Compliant status

Substitute parts are grouped into two categories:

Parametric Equivalent: MC7809CTG from onsemi matches all critical parameters with identical electrical specifications and active product status, providing direct replacement capability.

Direct and Similar Manufacturers: L7809ACV, L7809CV, L78M09CV, and L78S09CV from STMicroelectronics provide functional equivalence with variations in output current capacity and PSRR performance. These parts maintain the same 9V output, TO-220-3 package, and protection features, but differ in current ratings and quiescent current specifications.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: MC7809CTG from onsemi is the preferred substitute. It maintains identical electrical specifications to the MC7809ACTG while offering active product status, ensuring long-term availability and supply chain stability. Both devices are ROHS3 compliant and REACH unaffected.

Secondary Options: L7809ACV and L7809CV from STMicroelectronics provide functional equivalence with higher output current capacity (1.5A), suitable for applications requiring additional current margin. Both maintain the same 9V output, TO-220-3 package, and protection features. L7809ACV matches the quiescent current specification of the original part at 6 mA.

Current-Limited Alternatives: L78M09CV (500mA) is suitable only for applications with reduced current requirements below 1A. L78S09CV (2A) accommodates higher current demands and extends operating temperature to 150°C, with enhanced over-current protection.

All substitute parts maintain ROHS3 compliance and are suitable for direct PCB replacement without design modification, provided output current requirements do not exceed the specified ratings.

Frequently Asked Questions (FAQ)

Q: Can MC7809CTG directly replace MC7809ACTG? A: Yes. MC7809CTG is a parametric equivalent with identical output voltage (9V), current rating (1A), package (TO-220-3), and protection features. The primary difference is product status: MC7809CTG is active while MC7809ACTG is obsolete.

Q: What is the difference between L7809ACV and L7809CV? A: Both deliver 1.5A at 9V in TO-220-3 packages. L7809ACV has quiescent current of 6 mA and PSRR of 61dB, while L7809CV has quiescent current of 8 mA and PSRR of 55dB. L7809ACV more closely matches the original MC7809ACTG specifications.

Q: Can L78S09CV replace MC7809ACTG? A: L78S09CV is mechanically compatible (TO-220-3 package) and electrically compatible (9V output, same protection features). However, it provides 2A output current versus the original 1A specification. It is suitable for applications requiring higher current capacity and extended temperature operation to 150°C.

Q: Why is L78M09CV not recommended as a primary substitute? A: L78M09CV provides only 500mA output current, which is below the original 1A specification. It is suitable only for applications with reduced current demands.

Q: Are all substitute parts RoHS compliant? A: Yes. All listed substitute parts are ROHS3 compliant and REACH unaffected, maintaining regulatory compliance equivalent to the original MC7809ACTG.

Q: What is the impact of different PSRR values on substitution? A: PSRR (Power Supply Rejection Ratio) affects noise filtering performance. MC7809ACTG and MC7809CTG both provide 61dB at 120Hz. Substitutes with lower PSRR values (L7809CV at 55dB, L78M09CV at 56dB, L78S09CV at 47dB) may exhibit reduced noise rejection in sensitive applications.

Q: Can these parts be used in new designs or only as replacements? A: MC7809CTG is recommended for new designs due to active product status. Other substitutes are obsolete and should be used only for legacy system support or when specific performance characteristics are required.