4N23U Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N23U is an optoisolator transistor with base output manufactured by TT Electronics/Optek Technology. It provides 1000VDC isolation with a single channel configuration in a 6-LCC surface mount package. The device features a transistor output with accessible base terminal, enabling flexible circuit design for isolated switching applications.

The 4N23U is classified as obsolete. Locating equivalent or substitute components is necessary to support ongoing production requirements, maintenance operations, and new design implementations where this isolation topology remains functionally appropriate.

Substiute Parts

4N23U

TT Electronics/Optek TechnologyIn Stock: 10214N23U Datasheet

Current PartRFQ

4N24U

TT Electronics/Optek TechnologyIn Stock: 12094N24U Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 4N23U is determined by the following critical parameters:

• Voltage - Isolation: 1000VDC minimum
• Package / Case: 6-SMD, No Lead (6-LCC 6.22x4.32) for mechanical and thermal compatibility
• Output Type: Transistor with Base configuration
• Number of Channels: 1
• Input Type: DC
• Voltage - Output (Max): 35V or greater
• Vce Saturation (Max): 300mV or lower
• Operating Temperature Range: Must encompass or exceed -55°C ~ 125°C
• RoHS Status: ROHS3 Compliant

The 4N24U qualifies as a direct substitute based on identical isolation voltage, package configuration, output topology, and compliance certifications. Differences in Current Transfer Ratio and rise/fall time specifications do not preclude substitution when circuit design accommodates the higher performance characteristics of the 4N24U.

Parameter Comparison

Engineering Selection Recommendations

The 4N24U is the manufacturer-recommended substitute for the obsolete 4N23U. Both components maintain identical isolation voltage, package footprint, and output configuration, ensuring direct mechanical and electrical compatibility in existing circuit designs.

The 4N24U carries Active product status, providing assured long-term availability and supply chain continuity. Both components satisfy ROHS3 compliance and REACH unaffected status, meeting current regulatory requirements for electronic component procurement.

The 4N24U exhibits higher Current Transfer Ratio (100% @ 10mA versus 60% @ 10mA) and extended operating temperature range (-65°C ~ 125°C versus -55°C ~ 125°C). These enhanced specifications present no compatibility concerns for applications originally designed around 4N23U performance parameters.

Frequently Asked Questions (FAQ)

Q: Can the 4N24U be used as a direct replacement for the 4N23U in existing PCB designs?

A: Yes. The 4N24U maintains identical package geometry (6-LCC 6.22x4.32), pinout configuration, isolation voltage (1000VDC), and output topology (transistor with base). No PCB layout modifications are required.

Q: What are the key differences between the 4N23U and 4N24U?

A: The 4N24U provides higher Current Transfer Ratio (100% @ 10mA versus 60% @ 10mA), extended lower operating temperature limit (-65°C versus -55°C), and slightly slower rise/fall time (20µs versus 15µs). The 4N24U is Active status while the 4N23U is Obsolete.

Q: Are there any circuit design considerations when substituting the 4N24U for the 4N23U?

A: The higher Current Transfer Ratio of the 4N24U may reduce input current requirements for equivalent output switching performance. Circuit designs should accommodate this enhanced efficiency characteristic. The extended temperature range of the 4N24U provides additional operational margin.

Q: Do both components meet current compliance requirements?

A: Yes. Both the 4N23U and 4N24U are ROHS3 Compliant and REACH Unaffected, satisfying current regulatory standards for electronic component procurement and use.

Q: What is the moisture sensitivity level for these components?

A: Both components carry MSL 1 (Unlimited) classification, indicating no moisture sensitivity constraints during storage, handling, or assembly operations.