TOP233YN Equivalent & Substitute Parts

Part Overview

The TOP233YN is an offline flyback converter IC manufactured by Power Integrations, part of the TOPSwitch®-FX series. This component integrates a high-voltage power switch with control circuitry for isolated power supply applications operating at 66kHz to 132kHz switching frequency with 50W output power capability. The TOP233YN is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. Substitute parts must maintain functional compatibility across isolated flyback topology, switching frequency range, fault protection features, and thermal operating range.

Substiute Parts

TOP233YN

Power IntegrationsIn Stock: 1962TOP233YN Datasheet

Current PartRFQ

TOP264EG

Power IntegrationsIn Stock: 20825TOP264EG Datasheet

MFR RecommendedRFQ

TOP243YN

Power IntegrationsIn Stock: 57383TOP243YN Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TOP233YN is determined by the following critical parameters:

Primary Substitution Criteria:

• Topology: Flyback converter architecture
• Output Isolation: Isolated configuration
• Switching Frequency Range: 66kHz to 132kHz operation
• Fault Protection: Current Limiting, Over Temperature, Over Voltage minimum
• Control Features: Frequency Control capability
• Operating Temperature Range: -40°C to 150°C (TJ)
• Compliance: RoHS Compliant, REACH Unaffected

Secondary Compatibility Factors:

• Voltage Breakdown Rating: 700V or higher
• Power Rating: Equal to or greater than 50W
• Package Type: Through-hole mounting compatible with PCB design
• Moisture Sensitivity: MSL 1 (Unlimited)

The TOP233YN has two identified substitutes: TOP243YN (similar part, not for new designs) and TOP264EG (manufacturer-recommended active substitute).

Parameter Comparison

Engineering Selection Recommendations

For New Designs: The TOP264EG is the manufacturer-recommended substitute for the obsolete TOP233YN. This part is classified as Active product status, ensuring long-term availability and continued manufacturing support. The TOP264EG operates within the same switching frequency range (66kHz, 132kHz), maintains identical operating temperature specifications (-40°C to 150°C TJ), and provides enhanced fault protection including Over Load and Short Circuit detection beyond the TOP233YN baseline. The increased power rating (62W versus 50W) and higher voltage breakdown rating (725V versus 700V) provide design margin for existing applications.

For Existing Production: The TOP243YN provides functional compatibility with the TOP233YN across all critical parameters: identical topology, switching frequency range, operating temperature, and core fault protection features. However, TOP243YN is classified as Not For New Designs, indicating limited future availability. The TOP243YN exhibits lower power rating (45W versus 50W) and reduced duty cycle (66.5% versus 78%), requiring design verification for applications operating at maximum TOP233YN specifications.

Package Considerations: The TOP233YN uses TO-220-7 package with 5 leads. The TOP243YN uses TO-220-7 package with 6 leads, requiring PCB layout modification. The TOP264EG uses eSIP-7C package (7-SSIP with exposed pad), necessitating complete PCB redesign but offering improved thermal performance through the exposed pad feature.

Compliance Status: All three parts maintain RoHS Compliance and REACH Unaffected status, suitable for regulated markets and applications requiring environmental compliance documentation.

Frequently Asked Questions (FAQ)

Q: Can TOP233YN be directly replaced with TOP243YN without PCB modification? A: No. While both use TO-220-7 package, TOP233YN has 5 leads and TOP243YN has 6 leads. Pin configuration differences require PCB layout changes. Pinout verification against manufacturer datasheets is mandatory before substitution.

Q: What is the primary advantage of TOP264EG over TOP233YN? A: TOP264EG is an active product with manufacturer support, whereas TOP233YN is obsolete. TOP264EG provides enhanced fault protection (Over Load and Short Circuit detection), higher power rating (62W), and improved thermal management through eSIP-7C package with exposed pad. These features support long-term production continuity.

Q: Is TOP264EG suitable for applications designed for TOP233YN 50W output? A: Yes. TOP264EG 62W rating exceeds TOP233YN 50W requirement. Switching frequency range (66kHz, 132kHz), operating temperature (-40°C to 150°C TJ), and isolation characteristics are compatible. However, package change from TO-220-7 to eSIP-7C requires PCB redesign.

Q: Why does TOP243YN have lower power rating (45W) than TOP233YN (50W)? A: Power rating differences reflect design variations within the TOPSwitch series. TOP243YN duty cycle (66.5%) is lower than TOP233YN (78%), affecting maximum power delivery capability. Applications requiring full 50W output cannot use TOP243YN without design modification.

Q: Are all three parts RoHS compliant? A: Yes. TOP233YN, TOP243YN, and TOP264EG are all RoHS Compliant with MSL 1 (Unlimited) moisture sensitivity rating, suitable for standard manufacturing and storage conditions.

Q: What is the difference between switching frequency specifications "66kHz ~ 132kHz" and "66kHz, 132kHz"? A: TOP233YN and TOP243YN support continuous frequency range from 66kHz to 132kHz. TOP264EG operates at discrete frequencies of 66kHz or 132kHz. This difference may affect design flexibility in frequency selection but does not prevent functional substitution for applications using either endpoint frequency.

Q: Which substitute part should be selected for new product development? A: TOP264EG is the recommended choice for new designs. Active product status ensures manufacturing continuity, enhanced protection features support reliability requirements, and higher power rating provides design margin. Package change requires PCB redesign but offers thermal performance benefits.