MC7912ACT Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The MC7912ACT is a linear voltage regulator IC manufactured by onsemi, designed to provide a fixed negative 12V output at 1A current capacity in a TO-220-3 package. This device is classified as obsolete, which necessitates identification of equivalent and substitute parts for ongoing design support and procurement.

The MC7912ACT serves applications requiring negative voltage regulation with thermal and overcurrent protection. Due to its obsolete status, active alternatives from onsemi and cross-manufacturer equivalents are available to maintain design continuity.

Substiute Parts

MC7912ACT

onsemiIn Stock: 883MC7912ACT Datasheet

Current PartRFQ

MC7912ACTG

onsemiIn Stock: 2296MC7912ACTG Datasheet

DirectRFQ

MC7912CTG

onsemiIn Stock: 5003MC7912CTG Datasheet

Parametric EquivalentRFQ

L7912ACV

STMicroelectronicsIn Stock: 25408L7912ACV Datasheet

SimilarRFQ

L7912CV

STMicroelectronicsIn Stock: 75321L7912CV Datasheet

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LM7912CT/NOPB

Texas InstrumentsIn Stock: 2879LM7912CT/NOPB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MC7912ACT is determined by the following critical parameters:

• Output Voltage: -12V fixed output (all substitutes maintain this specification)
• Package / Case: TO-220-3 form factor (all substitutes use identical mechanical package)
• Mounting Type: Through Hole (all substitutes are through-hole mounted)
• Operating Temperature Range: 0°C ~ 125°C (all substitutes support this range)
• Input Voltage Rating: -35V maximum (all substitutes rated to this specification)

Substitutes are grouped into two categories:

Direct Equivalents (onsemi): MC7912ACTG and MC7912CTG maintain identical electrical specifications and differ only in product status (active vs. obsolete) and packaging format (tube).

Cross-Manufacturer Equivalents (STMicroelectronics, Texas Instruments): L7912ACV, L7912CV, and LM7912CT/NOPB provide -12V output in TO-220-3 packages with enhanced current capacity (1.5A) and improved electrical characteristics, making them suitable for applications with higher current demands or stricter performance requirements.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Identical Specifications)

MC7912ACTG and MC7912CTG are direct onsemi equivalents with identical electrical performance to the MC7912ACT. Both are active products with ROHS3 compliance, making them suitable for new designs and legacy system maintenance. MC7912ACTG offers higher inventory availability (2190 pcs) compared to MC7912CTG (4900 pcs).

For Enhanced Performance Applications

L7912ACV, L7912CV, and LM7912CT/NOPB provide increased output current capacity (1.5A vs. 1A), lower dropout voltage (1.1V vs. 1.3V), and improved PSRR characteristics. These cross-manufacturer alternatives are appropriate for applications requiring higher current delivery or superior noise rejection. All three are active products with ROHS3 compliance.

LM7912CT/NOPB from Texas Instruments offers the highest PSRR specification (70dB at 120Hz) and lowest quiescent current (1.5mA), making it optimal for noise-sensitive applications.

Compliance Considerations

All substitute parts are ROHS3 compliant and REACH unaffected, meeting modern environmental and regulatory requirements. The MC7912ACT, being non-compliant, should be replaced in new designs requiring regulatory certification.

Frequently Asked Questions (FAQ)

Q: Can MC7912ACTG directly replace MC7912ACT without circuit modification?

A: Yes. MC7912ACTG maintains identical electrical specifications, output voltage (-12V), current rating (1A), input voltage range (-35V max), and TO-220-3 package configuration. No circuit changes are required.

Q: What is the difference between MC7912ACTG and MC7912CTG?

A: Both are onsemi equivalents with identical electrical performance. The primary difference is packaging format: MC7912ACTG is supplied in tube packaging, while MC7912CTG is also tube-packaged. Both are active products with ROHS3 compliance.

Q: Can L7912ACV or L7912CV be used as drop-in replacements?

A: Yes, with design considerations. These STMicroelectronics parts maintain the -12V output, TO-220-3 package, and -35V input rating. However, they provide 1.5A output current versus 1A in the MC7912ACT. The lower dropout voltage (1.1V vs. 1.3V) and improved PSRR (60dB vs. 61dB) are beneficial. No circuit modification is required for mechanical or electrical compatibility.

Q: What are the advantages of LM7912CT/NOPB over the onsemi alternatives?

A: LM7912CT/NOPB from Texas Instruments offers superior PSRR (70dB at 120Hz), lower quiescent current (1.5mA), and 1.5A output capacity. These characteristics make it preferable for applications with stringent noise requirements or higher current demands. The TO-220-3 package ensures mechanical compatibility.

Q: Are all substitute parts RoHS compliant?

A: All substitute parts (MC7912ACTG, MC7912CTG, L7912ACV, L7912CV, LM7912CT/NOPB) are ROHS3 compliant. The original MC7912ACT is non-compliant, making substitution necessary for designs requiring regulatory certification.

Q: Which substitute offers the best inventory availability?

A: L7912CV from STMicroelectronics has the highest inventory (75,300 pcs), followed by MC7912CTG (4,900 pcs) and L7912ACV (25,300 pcs). MC7912ACTG has 2,190 pcs available, and LM7912CT/NOPB has 2,841 pcs.

Q: Can these parts be used interchangeably in existing PCB designs?

A: Yes. All substitute parts use the TO-220-3 package with identical pin configuration and through-hole mounting. PCB layouts require no modification for mechanical compatibility. Electrical performance is maintained or improved across all substitutes.