HCPL2731S Equivalent & Substitute Parts

Part Overview

The HCPL2731S is a 2-channel optoisolator with Darlington output manufactured by onsemi, rated for 2500Vrms isolation voltage. This component is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production support. The HCPL2731S provides DC input isolation with 60mA output current per channel and operates across the industrial temperature range of -40°C to 85°C in an 8-SMD surface mount package.

Substiute Parts

HCPL2731S

onsemiIn Stock: 1131HCPL2731S Datasheet

Current PartRFQ

HCPL2731SM

onsemiIn Stock: 3259HCPL2731SM Datasheet

MFR RecommendedRFQ

HCPL-2731#300

Broadcom LimitedIn Stock: 1098HCPL-2731#300 Datasheet

SimilarRFQ

HCPL-2731#500

Broadcom LimitedIn Stock: 1154HCPL-2731#500 Datasheet

SimilarRFQ

HCPL-273L-500E

Broadcom LimitedIn Stock: 781HCPL-273L-500E Datasheet

SimilarRFQ

HCPL-4731#300

Broadcom LimitedIn Stock: 1135HCPL-4731#300 Datasheet

SimilarRFQ

HCPL-4731-300E

Broadcom LimitedIn Stock: 2481HCPL-4731-300E Datasheet

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HCPL-4731-320E

Broadcom LimitedIn Stock: 875HCPL-4731-320E Datasheet

SimilarRFQ

HCPL-4731-500E

Broadcom LimitedIn Stock: 1110HCPL-4731-500E Datasheet

SimilarRFQ

HCPL-4731-520E

Broadcom LimitedIn Stock: 1088HCPL-4731-520E Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution for the HCPL2731S is determined by the following critical parameters:

• Number of Channels: Must be 2 channels
• Output Type: Must be Darlington output
• Voltage - Isolation: Minimum 2500Vrms (higher ratings are acceptable)
• Current - Output / Channel: Minimum 60mA
• Voltage - Output (Max): Minimum 18V
• Current Transfer Ratio (Min): Minimum 500% @ 1.6mA
• Package / Case: 8-SMD, Gull Wing form factor
• Input Type: DC input

Substitute parts are grouped into two categories: MFR Recommended (direct upgrade path) and Similar (functionally equivalent with noted parameter variations).

Parameter Comparison

Engineering Selection Recommendations

MFR Recommended Substitute:

HCPL2731SM is the primary upgrade path for HCPL2731S applications. This onsemi part maintains manufacturer continuity and increases isolation voltage to 5000Vrms while preserving all critical electrical parameters. Operating temperature extends to 100°C, providing enhanced thermal margin. ROHS3 compliance is maintained. This part is active in production with 3240 units in stock.

Similar Substitutes - Broadcom Limited Options:

The HCPL-2731 series (HCPL-2731#300, HCPL-2731#500) and HCPL-273L-500E provide 3750Vrms isolation with identical 2-channel Darlington output configuration. These parts are active and ROHS3 compliant (HCPL-273L-500E only). Operating temperature is limited to 0°C ~ 70°C, which may restrict use in extended industrial temperature applications. HCPL-2731#300 and HCPL-2731#500 are RoHS non-compliant.

The HCPL-4731 series (HCPL-4731#300, HCPL-4731-300E, HCPL-4731-500E, HCPL-4731-520E) and HCPL-4731-320E offer higher current transfer ratios (600% minimum @ 500µA) with 3750Vrms or 5000Vrms isolation. These parts feature lower forward current requirements (10mA maximum) and lower forward voltage (1.25V typical). All HCPL-4731 variants with "-E" suffix are ROHS3 compliant. Operating temperature is limited to 0°C ~ 70°C.

Compliance Considerations:

For applications requiring ROHS3 compliance, HCPL2731SM, HCPL-273L-500E, HCPL-4731-300E, HCPL-4731-320E, HCPL-4731-500E, and HCPL-4731-520E are suitable. HCPL-2731#300, HCPL-2731#500, and HCPL-4731#300 are RoHS non-compliant.

For applications requiring extended temperature operation (-40°C to 85°C or higher), HCPL2731SM (-40°C ~ 100°C) is the only substitute meeting this requirement. All Broadcom alternatives are limited to 0°C ~ 70°C.

Frequently Asked Questions (FAQ)

Q: Can HCPL2731SM directly replace HCPL2731S?

A: Yes. HCPL2731SM is the MFR recommended substitute from onsemi. It maintains the same 2-channel Darlington output, 8-SMD package, and electrical interface while upgrading isolation voltage from 2500Vrms to 5000Vrms and extending operating temperature to 100°C. ROHS3 compliance is maintained.

Q: What is the key difference between HCPL-2731 and HCPL-4731 series?

A: The HCPL-4731 series features higher current transfer ratio (600% minimum @ 500µA versus 500% @ 1.6mA for HCPL-2731). HCPL-4731 parts require lower input forward current (10mA maximum versus 12-20mA) and operate with lower forward voltage (1.25V typical versus 1.3-1.5V). Both series provide 2-channel Darlington output with 60mA per channel.

Q: Are all substitute parts available in the same package?

A: All listed substitutes use 8-SMD, Gull Wing package format, maintaining PCB layout compatibility with HCPL2731S.

Q: Which substitute is suitable for -40°C to 85°C operation?

A: HCPL2731SM is the only substitute supporting the full -40°C to 85°C temperature range, extending to 100°C maximum. All Broadcom alternatives (HCPL-2731 and HCPL-4731 series) are limited to 0°C ~ 70°C operation.

Q: What isolation voltage options are available?

A: HCPL2731SM provides 5000Vrms. HCPL-2731 series and most HCPL-4731 variants provide 3750Vrms. HCPL-4731-320E and HCPL-4731-520E provide 5000Vrms. All exceed the original 2500Vrms specification.

Q: Are there RoHS compliance differences among substitutes?

A: HCPL2731SM, HCPL-273L-500E, HCPL-4731-300E, HCPL-4731-320E, HCPL-4731-500E, and HCPL-4731-520E are ROHS3 compliant. HCPL-2731#300, HCPL-2731#500, and HCPL-4731#300 are RoHS non-compliant.

Q: What is the difference between HCPL-4731-300E and HCPL-4731-320E?

A: Both parts are ROHS3 compliant with identical electrical characteristics. HCPL-4731-320E provides 5000Vrms isolation versus 3750Vrms for HCPL-4731-300E. Both operate at 0°C ~ 70°C.