TOP234YN Equivalent & Substitute Parts

Part Overview

The TOP234YN is an offline flyback converter IC manufactured by Power Integrations, designed for isolated power supply applications. This device operates in the TOPSwitch®-FX series and delivers 75 W of power using a flyback topology with integrated switching functionality. The TOP234YN is classified as obsolete, making identification of active equivalent parts essential for new designs and production continuity. Substitute parts must maintain functional compatibility across topology, isolation characteristics, switching frequency, fault protection capabilities, and thermal operating range.

Substiute Parts

TOP234YN

Power IntegrationsIn Stock: 5103TOP234YN Datasheet

Current PartRFQ

TOP264EG

Power IntegrationsIn Stock: 20825TOP264EG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TOP234YN is determined by strict alignment of the following critical parameters:

Topology & Isolation: Both the main part and substitute must operate as isolated flyback converters with internal switching capability.

Voltage Rating: The substitute breakdown voltage (725V for TOP264EG) must equal or exceed the original specification (700V).

Switching Frequency: The substitute must support the same frequency range or compatible subset (66kHz, 132kHz).

Duty Cycle: The substitute must operate at the specified duty cycle (78%).

Fault Protection: The substitute must include at minimum the protection features of the original: Current Limiting, Over Temperature, and Over Voltage. Additional protections (Over Load, Short Circuit) in the substitute do not disqualify compatibility.

Control Features: Frequency Control capability must be present in the substitute.

Operating Temperature Range: The substitute must support the full operating range (-40°C ~ 150°C TJ).

Compliance & Certifications: Both parts must maintain RoHS compliance and MSL rating of 1.

Mounting & Package: Through-hole mounting is required; package form factor differences are acceptable if electrical and thermal characteristics are preserved.

The TOP264EG meets all substitution criteria as an active product in the TOPSwitch®-JX series, offering enhanced protection features and improved availability.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: TOP264EG

The TOP264EG is the recommended substitute for the obsolete TOP234YN. Both devices are manufactured by Power Integrations and share identical topology, isolation characteristics, switching frequency capability, duty cycle, control features, and thermal operating range. The TOP264EG operates at a higher breakdown voltage (725V vs. 700V), providing enhanced voltage margin. Enhanced fault protection in the TOP264EG (addition of Over Load and Short Circuit protection) exceeds the original specification without introducing incompatibility.

Critical Design Consideration: The TOP264EG is rated for 62 W maximum power output, compared to the TOP234YN's 75 W rating. Applications requiring the full 75 W output capacity must conduct thermal and electrical analysis to confirm the substitute meets power delivery requirements. For applications operating below 62 W, the TOP264EG provides direct functional substitution.

Compliance & Availability: Both parts maintain RoHS compliance and unlimited moisture sensitivity level (MSL 1). The TOP264EG is currently in active production with 20,760 units in stock, ensuring supply continuity compared to the obsolete TOP234YN status.

Package Consideration: The TOP264EG uses eSIP-7C packaging (7-SSIP, 6 Leads, Exposed Pad) versus the TOP234YN's TO-220-7 package. PCB layout and thermal management design must accommodate the different package form factor and exposed pad thermal characteristics.

Frequently Asked Questions (FAQ)

Q: Can the TOP264EG directly replace the TOP234YN without circuit modifications?

A: The TOP264EG provides functional substitution for isolated flyback converter applications with identical topology, switching frequency, duty cycle, and control features. However, the lower power rating (62 W vs. 75 W) and different package form factor (eSIP-7C vs. TO-220-7) require design review. Applications operating below 62 W output can proceed with substitution; higher-power applications require thermal and electrical analysis.

Q: What is the significance of the higher breakdown voltage in the TOP264EG?

A: The TOP264EG's 725V breakdown voltage exceeds the TOP234YN's 700V specification, providing additional voltage margin for transient protection and component reliability. This represents an enhancement rather than a limitation for substitution purposes.

Q: Are the fault protection differences between TOP234YN and TOP264EG significant?

A: The TOP264EG includes additional fault protection features (Over Load and Short Circuit protection) beyond the TOP234YN's protection set (Current Limiting, Over Temperature, Over Voltage). These enhancements improve system reliability and do not create incompatibility; they represent a superset of the original protection capabilities.

Q: How does the package change from TO-220-7 to eSIP-7C affect substitution?

A: Package form factor differences require PCB layout redesign, including footprint modification, thermal pad routing, and lead spacing adjustments. The eSIP-7C package includes an exposed pad for enhanced thermal dissipation. Mechanical compatibility cannot be assumed; layout validation is required before production implementation.

Q: Is the TOP264EG suitable for applications requiring the full 75 W output of the TOP234YN?

A: The TOP264EG is rated for 62 W maximum output. Applications requiring 75 W output must conduct thermal analysis and power delivery verification. If the application can operate within the 62 W limit, substitution is valid; otherwise, alternative parts must be evaluated.

Q: What compliance certifications apply to the TOP264EG as a substitute?

A: The TOP264EG maintains RoHS compliance, MSL rating of 1 (Unlimited), REACH Unaffected status, and EAR99 ECCN classification, matching the TOP234YN's compliance profile. No additional certification barriers exist for substitution.

Q: Why is the TOP234YN classified as obsolete?

A: The TOP234YN is part of the legacy TOPSwitch®-FX series. Power Integrations has transitioned to the TOPSwitch®-JX series (represented by TOP264EG), which offers enhanced protection features and improved performance characteristics. The TOP264EG represents the active product line continuation.