MOC3021TM Equivalent & Substitute Parts

Part Overview

The MOC3021TM is a 6-DIP optoisolator with triac output manufactured by onsemi, rated for 4170Vrms isolation voltage. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The MOC3021TM serves as a random-phase triac driver in isolation applications requiring single-channel optocoupling with through-hole mounting.

Substiute Parts

MOC3021TM

onsemiIn Stock: 1069MOC3021TM Datasheet

Current PartRFQ

MOC3021TVM

Fairchild SemiconductorIn Stock: 12939MOC3021TVM Datasheet

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IS3020

Isocom Components 2004 LTDIn Stock: 45237IS3020 Datasheet

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IS3021

Isocom Components 2004 LTDIn Stock: 45365IS3021 Datasheet

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IS3022

Isocom Components 2004 LTDIn Stock: 45455IS3022 Datasheet

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MOC3020G

Isocom Components 2004 LTDIn Stock: 1142MOC3020G Datasheet

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MOC3021G

Isocom Components 2004 LTDIn Stock: 1174MOC3021G Datasheet

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MOC3022G

Isocom Components 2004 LTDIn Stock: 1031MOC3022G Datasheet

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MOC3023G

Isocom Components 2004 LTDIn Stock: 1193MOC3023G Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution for the MOC3021TM is determined by the following critical parameters:

• Output Type: Triac (all substitutes must be triac-output optoisolators)
• Number of Channels: 1 (single-channel requirement)
• Mounting Type: Through Hole (PCB compatibility)
• Package / Case: 6-DIP form factor
• Voltage - Isolation: Minimum 4170Vrms (electrical isolation requirement)
• Current - LED Trigger (Ift): Maximum 15mA (input drive capability)
• Current - Hold (Ih): 100µA typical (holding current specification)
• Voltage - Forward (Vf): Approximately 1.15V (LED forward voltage)
• Current - DC Forward (If): Maximum 60mA (LED current rating)
• Operating Temperature: -40°C to 85°C minimum range

Substitutes are grouped into two categories:

Direct Functional Equivalent: MOC3021TVM (onsemi/Fairchild Semiconductor) maintains identical electrical specifications and 6-DIP package dimensions (0.400", 10.16mm).

Compatible Alternatives with Enhanced Specifications: IS3020, IS3021, IS3022 (Isocom Components) offer higher isolation voltage (5300Vrms) and improved temperature range (-40°C to 100°C) but feature different package dimensions (6-DIP 0.300", 7.62mm) and varying LED trigger current ratings.

Pin-Compatible Variants: MOC3020G, MOC3021G, MOC3022G, MOC3023G (Isocom Components) share the 6-DIP (0.400", 10.16mm) package footprint but specify isolation voltage as 7.5Vpk with differing LED trigger current requirements.

Parameter Comparison

Engineering Selection Recommendations

MOC3021TVM is the primary direct substitute for MOC3021TM. Both parts maintain identical electrical specifications (4170Vrms isolation, 15mA LED trigger current, 60mA forward current) and identical 6-DIP package dimensions (0.400", 10.16mm). MOC3021TVM is manufactured by Fairchild Semiconductor and carries active product status with UL and IEC/EN/DIN approvals, providing superior long-term availability compared to the obsolete MOC3021TM.

IS3021 is a compatible alternative when higher isolation voltage (5300Vrms) and extended operating temperature range (-40°C to 100°C) are acceptable. IS3021 matches the 15mA LED trigger current specification but features a smaller 6-DIP package (0.300", 7.62mm), requiring PCB layout verification. IS3021 is ROHS3 compliant and actively manufactured by Isocom Components.

MOC3021G provides pin-compatible substitution with identical 6-DIP package dimensions (0.400", 10.16mm) and matching 15mA LED trigger current. MOC3021G is manufactured by Isocom Components with active status, UL and VDE approvals, and ROHS3 compliance. The isolation voltage specification differs (7.5Vpk versus 4170Vrms), requiring circuit-level evaluation.

IS3022 offers the lowest LED trigger current (10mA) among active substitutes with 5300Vrms isolation and extended temperature range. IS3022 uses the smaller 6-DIP package (0.300", 7.62mm) and is ROHS3 compliant.

MOC3022G and MOC3023G provide alternatives with progressively lower LED trigger current requirements (10mA and 5mA respectively) while maintaining the standard 6-DIP package footprint (0.400", 10.16mm). Both are actively manufactured with UL and VDE approvals.

Frequently Asked Questions (FAQ)

Q: Can MOC3021TVM directly replace MOC3021TM without circuit modification?

A: Yes. MOC3021TVM is electrically and mechanically identical to MOC3021TM. Both specify 4170Vrms isolation voltage, 15mA maximum LED trigger current, 60mA maximum forward current, and identical 6-DIP package dimensions (0.400", 10.16mm). No circuit redesign is required.

Q: What is the primary difference between IS3021 and MOC3021TM?

A: IS3021 provides higher isolation voltage (5300Vrms versus 4170Vrms) and extended operating temperature range (-40°C to 100°C versus -40°C to 85°C). However, IS3021 uses a smaller 6-DIP package (0.300", 7.62mm versus 0.400", 10.16mm), which may require PCB layout changes. LED trigger current specification is identical at 15mA maximum.

Q: Are the Isocom MOC302x series parts (MOC3020G, MOC3021G, MOC3022G, MOC3023G) direct replacements?

A: MOC3021G is pin-compatible with identical 6-DIP package dimensions (0.400", 10.16mm) and matching 15mA LED trigger current. However, the isolation voltage specification differs (7.5Vpk versus 4170Vrms), requiring circuit evaluation to confirm suitability. MOC3020G, MOC3022G, and MOC3023G have different LED trigger current ratings (30mA, 10mA, and 5mA respectively) and should be selected based on specific input drive requirements.

Q: What does the package dimension difference (0.400" versus 0.300") mean for PCB compatibility?

A: The 0.400" (10.16mm) package (MOC3021TM, MOC3021TVM, MOC3020G, MOC3021G, MOC3022G, MOC3023G) and 0.300" (7.62mm) package (IS3020, IS3021, IS3022) have different pin spacing. PCBs designed for 0.400" spacing cannot accommodate 0.300" parts without layout modification. Verify footprint compatibility before substitution.

Q: Which substitute offers the best long-term availability?

A: MOC3021TVM (Fairchild Semiconductor) and the Isocom series (IS3020, IS3021, IS3022, MOC3020G, MOC3021G, MOC3022G, MOC3023G) all carry active product status. MOC3021TVM is recommended for direct replacement due to identical specifications and established supply chain presence.

Q: Are all substitute parts RoHS compliant?

A: MOC3021TVM compliance status is not specified in available data. All Isocom parts (IS3020, IS3021, IS3022, MOC3020G, MOC3021G, MOC3022G, MOC3023G) are ROHS3 compliant. Verify RoHS requirements for your application before final selection.

Q: What is the significance of LED trigger current (Ift) differences?

A: LED trigger current determines the input drive requirement. MOC3021TM and MOC3021TVM require 15mA maximum. IS3022 and MOC3022G require only 10mA, while MOC3023G requires 5mA. Lower trigger current reduces input circuit power dissipation. Higher trigger current parts (IS3020 at 30mA) require stronger input drivers. Select based on available input drive capability.