4N35M Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N35M is an optoisolator transistor with base output manufactured by Lite-On Inc., designed for high-voltage isolation applications. This component provides 3550Vrms isolation with a single channel, transistor output configuration, and 6-DIP through-hole packaging. The part is currently active in production with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent electrical performance, package compatibility, and isolation ratings meet or exceed the original specification requirements.

Substiute Parts

4N35M

Lite-On Inc.In Stock: 227174N35M Datasheet

Current PartRFQ

4N35G

Isocom Components 2004 LTDIn Stock: 12254N35G Datasheet

MFR RecommendedRFQ

4N35TVM

onsemiIn Stock: 43264N35TVM Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 4N35M optoisolator are qualified based on the following critical parameters:

• Package Compatibility: All substitutes must use 6-DIP (0.400", 10.16mm) through-hole packaging to ensure direct board-level replacement without layout modifications.
• Output Configuration: All substitutes must provide transistor output with base connection to maintain circuit interface compatibility.
• Isolation Voltage: Substitute parts must meet or exceed the 3550Vrms isolation rating of the original part.
• Current Transfer Ratio: Minimum 100% @ 10mA is required for functional equivalence.
• Vce Saturation: Maximum 300mV saturation voltage ensures compatible switching performance.
• Operating Temperature Range: Substitutes must support the -55°C to 100°C operating window or a compatible subset.
• Compliance: All substitutes must maintain RoHS3 compliance and EAR99 export classification.

Parameter Comparison

Engineering Selection Recommendations

Both 4N35G and 4N35TVM qualify as functional substitutes for the 4N35M based on package compatibility, output configuration, and compliance requirements.

4N35G (Isocom Components 2004 LTD): This substitute provides superior isolation voltage (5300Vrms versus 3550Vrms) and faster switching performance (2µs rise/fall time versus 3µs). It maintains identical current transfer ratio, saturation voltage, and operating temperature range. RoHS3 compliance and REACH unaffected status are confirmed. This part is suitable for applications requiring enhanced isolation margin.

4N35TVM (onsemi): This substitute provides intermediate isolation voltage (4170Vrms) with identical current transfer ratio and saturation voltage specifications. The operating temperature range is -40°C to 100°C, which covers the upper portion of the 4N35M range. RoHS3 compliance and REACH unaffected status are confirmed. This part is suitable for applications within the -40°C to 100°C temperature window.

Both substitutes maintain the 6-DIP through-hole package, transistor with base output configuration, and DC input type required for direct circuit replacement.

Frequently Asked Questions (FAQ)

Q: Can the 4N35G replace the 4N35M in all applications?

A: The 4N35G is electrically compatible as a direct substitute. It provides higher isolation voltage (5300Vrms) and faster switching (2µs versus 3µs), making it suitable for the same circuit topologies. Package and output configuration are identical. Verify that the application does not depend on specific timing characteristics that would be affected by the faster rise/fall time.

Q: What is the key difference between 4N35G and 4N35TVM?

A: The primary differences are isolation voltage (5300Vrms for 4N35G versus 4170Vrms for 4N35TVM) and operating temperature range (-55°C to 100°C for 4N35G versus -40°C to 100°C for 4N35TVM). Both maintain identical current transfer ratio and saturation voltage. Select based on isolation margin requirements and minimum operating temperature needs.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use 6-DIP (0.400", 10.16mm) through-hole packaging with identical pin configuration for transistor output with base connection. Direct board-level substitution is possible without layout modification.

Q: Do all substitutes meet RoHS3 compliance?

A: Yes. The 4N35M, 4N35G, and 4N35TVM are all RoHS3 compliant. The 4N35G and 4N35TVM additionally carry REACH unaffected status.

Q: What is the minimum isolation voltage requirement for substitution?

A: Substitute parts must meet or exceed the 3550Vrms isolation rating of the 4N35M. Both 4N35G (5300Vrms) and 4N35TVM (4170Vrms) satisfy this requirement.

Q: Can the 4N35TVM be used in applications requiring -55°C operation?

A: No. The 4N35TVM operating temperature range is -40°C to 100°C. For applications requiring -55°C operation, use the 4N35M or 4N35G, both rated to -55°C.