MOC81043SD Optoisolator Equivalent & Substitute Parts

Part Overview

The MOC81043SD is a 5300Vrms isolation optoisolator with transistor output manufactured by onsemi in a 6-SMD surface mount package. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The part delivers single-channel isolation with 50mA output current capability and operates across the -55°C to 100°C temperature range.

Substiute Parts

MOC81043SD

onsemiIn Stock: 898MOC81043SD Datasheet

Current PartRFQ

CNY17F4SR2VM

onsemiIn Stock: 2003CNY17F4SR2VM Datasheet

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MOC8104-X019T

Vishay Semiconductor Opto DivisionIn Stock: 3877MOC8104-X019T Datasheet

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MOC8104SM

Isocom Components 2004 LTDIn Stock: 1153MOC8104SM Datasheet

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MOC8104SMT&R

Isocom Components 2004 LTDIn Stock: 871MOC8104SMT&R Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MOC81043SD is determined by the following critical parameters:

• Isolation Voltage: Minimum 5300Vrms required for direct substitution
• Output Type: Transistor output mandatory
• Number of Channels: Single channel required
• Package / Case: 6-SMD, Gull Wing form factor
• Mounting Type: Surface mount compatibility
• Current - Output / Channel: Minimum 50mA capability
• Vce Saturation: Maximum 400mV acceptable
• Operating Temperature Range: Must encompass -55°C to 100°C or be compatible with application requirements

Based on these criteria, the following parts qualify as substitutes:

Direct Substitutes (Matching Isolation Voltage):

• MOC8104-X019T (onsemi/Vishay, 5300Vrms, Active status)

Functional Alternatives (Lower Isolation Voltage):

• CNY17F4SR2VM (onsemi, 4170Vrms, Active status, RoHS3 compliant)

Series Variants (Incomplete Specifications):

• MOC8104SM (Isocom Components, 7.5Vpk isolation, Active status)
• MOC8104SMT&R (Isocom Components, 7.5Vpk isolation, Active status)

Parameter Comparison

Engineering Selection Recommendations

MOC8104-X019T is the primary substitute for the obsolete MOC81043SD. Both parts maintain identical isolation voltage (5300Vrms), current transfer ratio specifications, output voltage limits, and operating temperature range. The MOC8104-X019T is manufactured by Vishay Semiconductor Opto Division and carries Active product status with RoHS3 compliance, ensuring long-term availability and regulatory alignment.

CNY17F4SR2VM serves as a functional alternative when isolation voltage requirements can be reduced to 4170Vrms. This onsemi part is Active and RoHS3 compliant. The lower isolation rating and higher maximum output voltage (70V vs. 30V) make it suitable for applications with reduced isolation demands. Operating temperature range is -40°C to 100°C, which excludes the lower -55°C extreme.

MOC8104SM and MOC8104SMT&R are Isocom Components variants with incomplete electrical specifications (isolation voltage listed as 7.5Vpk rather than Vrms, missing current transfer ratio data). These parts are Active and RoHS3 compliant but lack sufficient documented parameters for direct engineering comparison. Use only when application requirements align with available specifications and Isocom documentation is consulted.

Frequently Asked Questions (FAQ)

Q: Can MOC8104-X019T directly replace MOC81043SD without circuit modification?

A: Yes. Both parts share identical isolation voltage (5300Vrms), current transfer ratio range (160–256% @ 10mA), maximum output voltage (30V), output current (50mA), and operating temperature range (-55°C to 100°C). The 6-SMD, Gull Wing package and surface mount configuration are identical. Pin-to-pin compatibility requires verification against detailed pinout documentation.

Q: What is the key difference between MOC81043SD and CNY17F4SR2VM?

A: The primary difference is isolation voltage: MOC81043SD provides 5300Vrms while CNY17F4SR2VM provides 4170Vrms. CNY17F4SR2VM also offers higher maximum output voltage (70V vs. 30V) and has a narrower operating temperature range (-40°C to 100°C vs. -55°C to 100°C). Use CNY17F4SR2VM only in applications where 4170Vrms isolation is sufficient.

Q: Why are MOC8104SM and MOC8104SMT&R listed if specifications are incomplete?

A: These parts are listed because they appear in the original substitute list for MOC81043SD. However, the isolation voltage specification (7.5Vpk) differs significantly from the Vrms ratings of other parts, and critical parameters such as current transfer ratio are not documented. Engineering evaluation requires direct consultation with Isocom Components technical documentation.

Q: What packaging options are available for substitutes?

A: MOC8104-X019T and CNY17F4SR2VM are supplied in Tape & Reel (TR) format for automated assembly. MOC8104SM is supplied in Tube packaging. MOC8104SMT&R is supplied in Tape & Reel (TR). Select packaging based on production volume and assembly equipment compatibility.

Q: Are all substitute parts RoHS3 compliant?

A: MOC8104-X019T, CNY17F4SR2VM, MOC8104SM, and MOC8104SMT&R are all RoHS3 compliant. The original MOC81043SD does not list RoHS status. Compliance verification is recommended for applications subject to RoHS regulations.