4N49TX Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N49TX is a 1000VDC optoisolator transistor with base output in a TO-78-6 metal can package, manufactured by TT Electronics/Optek Technology. This component provides galvanic isolation for single-channel DC signal transmission with integrated base drive capability. The 4N49TX is classified as obsolete, making identification of active equivalent parts essential for ongoing system support and new design implementations.

Substiute Parts

4N49TX

TT Electronics/Optek TechnologyIn Stock: 8034N49TX Datasheet

Current PartRFQ

JANTX4N49

TT Electronics/Optek TechnologyIn Stock: 1529JANTX4N49 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 4N49TX is determined by strict equivalence across the following critical parameters:

• Isolation Voltage: 1000VDC minimum
• Number of Channels: Single channel only
• Output Configuration: Transistor with base drive
• Current Transfer Ratio Range: 200% to 1000% @ 1mA
• Maximum Output Specifications: 40V, 50mA per channel
• Saturation Voltage: 300mV maximum
• Package: TO-78-6 metal can through-hole mounting
• Operating Temperature: -55°C to 125°C

The JANTX4N49 meets all these criteria and is qualified as a direct substitute. This part maintains identical electrical performance while offering improved product status and compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The JANTX4N49 is the qualified substitute for the obsolete 4N49TX. Selection is based on the following engineering criteria:

Product Status: The 4N49TX is obsolete. The JANTX4N49 maintains active product status with ongoing manufacturer support and availability.

Electrical Equivalence: Both parts deliver identical isolation voltage, current transfer ratio specifications, output voltage and current ratings, and saturation characteristics. The JANTX4N49 demonstrates improved switching performance with maximum rise/fall times of 20µs compared to 25µs for the 4N49TX.

Compliance: The JANTX4N49 achieves ROHS3 compliance, whereas the 4N49TX is RoHS non-compliant. Both parts maintain REACH Unaffected status and EAR99 export classification.

Package Compatibility: Both parts use identical TO-78-6 metal can through-hole packaging, ensuring direct mechanical and electrical compatibility in existing PCB designs.

Frequently Asked Questions (FAQ)

Q: Can the JANTX4N49 replace the 4N49TX in existing designs?

A: Yes. The JANTX4N49 is electrically and mechanically equivalent to the 4N49TX. Both parts share identical isolation voltage, current transfer ratio specifications, output ratings, and TO-78-6 package configuration. Direct substitution is supported without circuit modification.

Q: What is the difference in switching performance between these parts?

A: The JANTX4N49 offers improved switching characteristics with maximum rise and fall times of 20µs, compared to 25µs for the 4N49TX. This represents a 20% performance improvement and may benefit applications requiring faster signal transitions.

Q: Does the JANTX4N49 meet RoHS requirements?

A: Yes. The JANTX4N49 is ROHS3 compliant. If RoHS compliance is required for your application, the JANTX4N49 is the appropriate selection over the non-compliant 4N49TX.

Q: Are there any package or pinout differences?

A: No. Both the 4N49TX and JANTX4N49 use the TO-78-6 metal can package with identical through-hole mounting configuration. No PCB layout modifications are required.

Q: What is the availability status of these parts?

A: The 4N49TX is obsolete with limited remaining inventory. The JANTX4N49 is an active product with current manufacturing and distribution support.