4N48A Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N48A is a 1000VDC optoisolator transistor with base output in a TO-78-6 metal can package, manufactured by TT Electronics/Optek Technology. This component is classified as obsolete, making identification of suitable substitutes essential for ongoing system support and new design implementations. The 4N48A provides single-channel isolation with transistor output configuration, commonly used in applications requiring high-voltage galvanic isolation with direct base drive capability.

Substiute Parts

4N48A

TT Electronics/Optek TechnologyIn Stock: 8884N48A Datasheet

Current PartRFQ

4N48

TT Electronics/Optek TechnologyIn Stock: 7164N48 Datasheet

MFR RecommendedRFQ

4N48

TT Electronics/Optek TechnologyIn Stock: 7164N48 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 4N48A is determined by strict equivalence across the following critical parameters:

• Isolation Voltage: 1000VDC minimum
• Number of Channels: Single channel (1)
• Output Configuration: Transistor with Base
• Package Type: TO-78-6 Metal Can
• Mounting Method: Through Hole
• Electrical Performance: Current Transfer Ratio 100–500% @ 1mA, Output voltage 40V maximum, Output current 50mA per channel
• Operating Temperature Range: -55°C to 125°C minimum

The 4N48 from TT Electronics/Optek Technology meets all substitution criteria. This part maintains identical electrical specifications, package configuration, and functional characteristics while offering active product status and improved compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The 4N48 is the direct substitute for the obsolete 4N48A. Both parts are manufactured by TT Electronics/Optek Technology and provide identical electrical and mechanical specifications. The 4N48 offers the advantage of active product status, ensuring continued availability and supply chain reliability. Additionally, the 4N48 achieves ROHS3 compliance, whereas the 4N48A is RoHS non-compliant. Both parts maintain equivalent REACH and ECCN classifications. For new designs or system replacements, the 4N48 is the appropriate selection based on product lifecycle status and regulatory compliance.

Frequently Asked Questions (FAQ)

Q: Can the 4N48 directly replace the 4N48A in existing applications?

A: Yes. The 4N48 provides identical electrical performance, isolation voltage, output current rating, and package configuration. Pin-for-pin compatibility is maintained, and no circuit modifications are required.

Q: What is the primary reason to substitute the 4N48A?

A: The 4N48A is classified as obsolete. The 4N48 is an active product from the same manufacturer with identical specifications, ensuring long-term availability and supply continuity.

Q: Are there any compliance differences between the two parts?

A: The 4N48 is ROHS3 compliant, while the 4N48A is RoHS non-compliant. Both parts maintain equivalent REACH and ECCN classifications. System compliance requirements should be evaluated based on application and regulatory jurisdiction.

Q: Is the TO-78-6 package still in production?

A: The TO-78-6 metal can package remains in use for optoisolator applications. Both the 4N48A and 4N48 utilize this package type, maintaining mechanical and thermal compatibility.

Q: What are the critical electrical parameters for substitution?

A: Substitution is valid when isolation voltage (1000VDC), number of channels (1), output type (transistor with base), current transfer ratio (100–500% @ 1mA), maximum output voltage (40V), and maximum output current (50mA) are maintained. The 4N48 meets all these requirements.