TOP249Y Equivalent & Substitute Parts

Part Overview

The TOP249Y is an offline flyback converter IC from Power Integrations' TOPSwitch®-GX series, designed for isolated power supply applications. This component integrates a high-voltage switch with control circuitry to deliver 250W power in a compact TO-220-7 package. The TOP249Y is classified as obsolete, making identification of compatible substitute parts essential for ongoing production support and design continuity.

Substiute Parts

TOP249Y

Power IntegrationsIn Stock: 1472TOP249Y Datasheet

Current PartRFQ

TOP249YN

Power IntegrationsIn Stock: 24211TOP249YN Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TOP249Y is determined by strict alignment with the following electrical and mechanical parameters:

Critical Substitution Criteria:

• Topology: Flyback converter architecture
• Output Isolation: Isolated configuration
• Voltage - Breakdown: 700V rating
• Power Rating: 250W capability
• Switching Frequency Range: 66kHz ~ 132kHz
• Duty Cycle: 66.8%
• Package Type: TO-220-7 Formed Leads, 6 Leads
• Mounting: Through Hole
• Fault Protection: Current Limiting, Over Temperature, Over Voltage
• Control Features: Frequency Control

The TOP249YN qualifies as a direct substitute based on identical electrical specifications and package configuration. Both parts operate within the same parameter envelope and maintain compatibility with existing circuit designs.

Parameter Comparison

Engineering Selection Recommendations

TOP249Y (Original Part): The TOP249Y is classified as obsolete. This part is suitable only for maintenance and repair of existing equipment where the original component specification must be maintained. New procurement should transition to the substitute part.

TOP249YN (Substitute Part): The TOP249YN is the direct electrical and mechanical equivalent of the TOP249Y. This part carries a "Not For New Designs" status but maintains full compatibility with existing TOP249Y circuit implementations. The TOP249YN is RoHS Compliant, providing environmental compliance advantages over the original TOP249Y. Inventory availability of TOP249YN (24,110 pcs) significantly exceeds TOP249Y (1,445 pcs), supporting production continuity.

For new designs, evaluation of current-generation TOPSwitch® products from Power Integrations is recommended to access the latest performance enhancements and compliance certifications.

Frequently Asked Questions (FAQ)

Q: Can TOP249YN be used as a direct replacement for TOP249Y in existing designs?

A: Yes. The TOP249YN is electrically and mechanically identical to the TOP249Y. Both parts share the same 700V breakdown voltage, 250W power rating, 66kHz ~ 132kHz switching frequency range, 66.8% duty cycle, TO-220-7 package configuration, and identical fault protection features. Pin-for-pin compatibility is maintained.

Q: What is the difference between TOP249Y and TOP249YN?

A: The primary differences are product status and RoHS compliance. The TOP249Y is obsolete and RoHS non-compliant. The TOP249YN is classified as "Not For New Designs" and is RoHS Compliant. Electrical and mechanical specifications are identical.

Q: Why is TOP249Y classified as obsolete?

A: Obsolescence reflects the product lifecycle status assigned by Power Integrations. The TOP249Y has been superseded in the manufacturer's product portfolio. The TOP249YN represents the transitional equivalent, though both parts are no longer recommended for new design implementations.

Q: Is the TO-220-7 package identical between TOP249Y and TOP249YN?

A: Yes. Both parts use the TO-220-7 Formed Leads package with 6 leads and through-hole mounting. PCB layout and thermal management considerations remain unchanged between the two parts.

Q: What are the key electrical parameters that define substitution eligibility?

A: Substitution is determined by matching: 700V breakdown voltage, 250W power rating, 66kHz ~ 132kHz switching frequency, 66.8% duty cycle, isolated flyback topology, frequency control features, and identical fault protection (current limiting, over temperature, over voltage).

Q: Can TOP249YN be used in new product designs?

A: The TOP249YN carries a "Not For New Designs" designation. While it functions identically to the TOP249Y, Power Integrations recommends evaluating current-generation TOPSwitch® converter ICs for new development projects to access enhanced features and extended product lifecycle support.