4N26S(TA)-V Optoisolator Equivalent & Substitute Parts

Part Overview

The 4N26S(TA)-V is an optoisolator transistor with base output manufactured by Everlight Electronics Co Ltd. This component provides 5000Vrms isolation in a 6-SMD surface mount package and is designed for DC input applications requiring transistor output with base connection. The part is currently active in production with 709 units in stock.

Substitute parts are necessary when the primary part becomes unavailable, when alternative sourcing is required for supply chain optimization, or when design flexibility permits selection from multiple qualified manufacturers offering equivalent electrical and mechanical characteristics.

Substiute Parts

4N26S(TA)-V

Everlight Electronics Co LtdIn Stock: 7784N26S(TA)-V Datasheet

Current PartRFQ

4N26S

Fairchild SemiconductorIn Stock: 90534N26S Datasheet

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4N26SM

Fairchild SemiconductorIn Stock: 221734N26SM Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 4N26S(TA)-V is determined by the following critical parameters:

Mandatory Matching Criteria:

• Number of Channels: 1
• Output Type: Transistor with Base
• Mounting Type: Surface Mount
• Package / Case: 6-SMD, Gull Wing
• Input Type: DC
• Vce Saturation (Max): 500mV

Allowable Parameter Ranges for Substitution:

• Voltage - Isolation: Minimum 5000Vrms (equal or higher acceptable)
• Current Transfer Ratio (Min): 20% @ 10mA (equal or higher acceptable)
• Voltage - Output (Max): 30V or higher (main part specifies 80V; substitutes at 30V are acceptable if application permits)
• Voltage - Forward (Vf) (Typ): 1.18V to 1.2V (minor variation acceptable)
• Current - DC Forward (If) (Max): 60mA or higher (equal or higher acceptable)
• Turn On / Turn Off Time (Typ): 2µs to 3µs (faster switching acceptable)
• Operating Temperature: Must include -55°C minimum; upper limit may vary

The substitute parts 4N26S (Fairchild Semiconductor) and 4N26SM (Fairchild Semiconductor) meet these criteria with documented electrical and mechanical compatibility.

Parameter Comparison

Engineering Selection Recommendations

4N26S (Fairchild Semiconductor) - Obsolete Status: This part is marked as obsolete and should not be selected for new designs or long-term production applications. While it meets electrical and mechanical compatibility criteria, its discontinued status creates supply chain risk. Use only when existing inventory is available and no alternative is feasible.

4N26SM (Fairchild Semiconductor) - Recommended Substitute: This part is the preferred substitute for the 4N26S(TA)-V. It maintains active product status, ensuring ongoing availability and supply chain stability. All critical parameters align with substitution requirements: identical channel count, output type, package configuration, and saturation voltage. The part is ROHS3 compliant and carries MSL rating equivalent to the primary part. The lower isolation voltage (4170Vrms versus 5000Vrms) is acceptable for applications not requiring the full 5000Vrms specification. Operating temperature range extends to -40°C minimum, which is suitable for most industrial applications.

Voltage - Output (Max) Consideration: Both Fairchild substitutes specify 30V maximum output voltage compared to the primary part's 80V. Applications requiring output voltages exceeding 30V must retain the 4N26S(TA)-V or conduct detailed circuit analysis to confirm compatibility.

Frequently Asked Questions (FAQ)

Q: Can 4N26SM replace 4N26S(TA)-V in all applications?

A: The 4N26SM is electrically and mechanically compatible for applications where the output voltage requirement does not exceed 30V and the operating temperature range of -40°C to 100°C is acceptable. If your circuit requires the full 80V output capability or operation below -40°C, the primary part 4N26S(TA)-V must be used.

Q: Why is the 4N26S (Fairchild) marked obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. While existing inventory may be available, this part should not be specified for new designs due to supply uncertainty and lack of ongoing manufacturing support.

Q: Are all three parts in the same physical package?

A: Yes. The 4N26S(TA)-V, 4N26S (Fairchild), and 4N26SM all use 6-SMD Gull Wing surface mount packaging, ensuring mechanical compatibility on PCBs designed for any of these parts.

Q: What is the significance of the isolation voltage difference between 4170Vrms and 5000Vrms?

A: Isolation voltage specifies the maximum voltage that can be safely applied between input and output circuits. The 4N26SM's 4170Vrms rating is lower than the primary part's 5000Vrms. Select the 4N26SM only if your application's isolation requirement is 4170Vrms or lower. Applications requiring 5000Vrms isolation must use the 4N26S(TA)-V.

Q: Is RoHS3 compliance maintained across all three parts?

A: Yes. All three parts are ROHS3 compliant, meeting environmental and regulatory requirements for commercial and industrial applications.

Q: What does MSL 1 (Unlimited) mean for moisture sensitivity?

A: MSL 1 indicates the component has unlimited shelf life and requires no special moisture control during storage or handling. This applies to the primary part 4N26S(TA)-V. Moisture sensitivity data for substitute parts should be verified from manufacturer documentation.