4N22U Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N22U is a 1000VDC optoisolator transistor with base output in a 6-LCC surface mount package, manufactured by TT Electronics/Optek Technology. This component provides galvanic isolation for DC signal transmission with integrated base drive capability. The 4N22U is currently classified as obsolete, necessitating identification of functionally equivalent active alternatives to maintain design continuity and ensure long-term component availability for new production and field replacements.

Substiute Parts

4N22U

TT Electronics/Optek TechnologyIn Stock: 10114N22U Datasheet

Current PartRFQ

4N24U

TT Electronics/Optek TechnologyIn Stock: 12094N24U Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 4N22U is determined by strict equivalence across the following critical parameters:

• Isolation Voltage: 1000VDC minimum
• Package Type: 6-LCC surface mount (6.22x4.32mm)
• Output Configuration: Transistor with base drive
• Input Type: DC
• Maximum Output Voltage: 35V
• Vce Saturation: 300mV maximum
• Compliance: ROHS3 and REACH requirements

The 4N24U meets all substitution criteria as an active, functionally equivalent replacement. Both parts share identical isolation voltage, package geometry, output topology, and electrical ratings. The primary distinction is the current transfer ratio specification and operating temperature range, which represent performance enhancements rather than incompatibilities.

Parameter Comparison

Engineering Selection Recommendations

The 4N24U is the direct active substitute for the 4N22U. Both components are manufactured by the same supplier and maintain identical mechanical and electrical interfaces. The 4N24U offers improved current transfer ratio performance (100% minimum versus 25% minimum) and extended low-temperature operating range (-65°C versus -55°C), representing performance enhancements with no design compatibility concerns.

Selection of the 4N24U eliminates obsolescence risk while maintaining full compliance with ROHS3 and REACH regulatory requirements. The active product status of the 4N24U ensures continued availability and manufacturing support.

Frequently Asked Questions (FAQ)

Q: Can the 4N24U directly replace the 4N22U in existing designs?

A: Yes. Both components share identical package geometry (6-LCC 6.22x4.32mm), isolation voltage (1000VDC), output configuration (transistor with base), and maximum electrical ratings (35V output, 300mV Vce saturation). Pin-to-pin compatibility is maintained.

Q: What is the primary difference between the 4N22U and 4N24U?

A: The 4N24U specifies a higher minimum current transfer ratio (100% @ 10mA versus 25% @ 10mA) and an extended low-temperature operating range (-65°C to 125°C versus -55°C to 125°C). These represent performance improvements with no negative impact on existing circuit designs.

Q: Why is the 4N22U classified as obsolete?

A: The 4N22U has been discontinued by the manufacturer. The 4N24U serves as the active production equivalent and is the recommended replacement for new designs and field replacements.

Q: Are there any compliance or certification differences?

A: No. Both the 4N22U and 4N24U maintain identical ROHS3 compliance and REACH unaffected status.

Q: What is the package type for both components?

A: Both components use a 6-LCC surface mount package with dimensions of 6.22mm × 4.32mm, classified as 6-SMD with no leads. This package type is suitable for automated assembly processes.