STR-Y6735 Equivalent & Substitute Parts

Part Overview

The STR-Y6735 is an offline switch flyback converter IC manufactured by Sanken Electric USA Inc., designed for isolated power management applications. This device operates in the 18.4kHz to 24.4kHz switching frequency range with a maximum power rating of 120W and supports supply voltages from 9.4V to 35V. The part is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing system support and new design considerations.

Substiute Parts

STR-Y6735

Sanken Electric USA Inc.In Stock: 2003STR-Y6735 Datasheet

Current PartRFQ

TOP246YN

Power IntegrationsIn Stock: 22608TOP246YN Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the STR-Y6735 is determined by the following critical parameters:

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

Package Compatibility: The TO-220-7 form factor is required for mechanical and thermal compatibility in existing designs.

Electrical Operating Range: Substitute parts must support the required supply voltage range and power delivery capability.

Fault Protection Features: Current limiting, over-temperature, and over-voltage protection are mandatory for system safety.

Compliance & Status: RoHS compliance and current product availability are essential for procurement and regulatory adherence.

The TOP246YN from Power Integrations qualifies as a substitute based on these criteria, sharing the same package type, isolated flyback topology, internal switch configuration, and comprehensive fault protection features.

Parameter Comparison

Engineering Selection Recommendations

The TOP246YN serves as a functional equivalent for the STR-Y6735 in isolated flyback converter applications. Both devices share identical package geometry (TO-220-7), mounting methodology (through-hole), and RoHS compliance status, enabling direct mechanical and regulatory compatibility.

The TOP246YN provides higher breakdown voltage (700V vs. 500V) and extended operating temperature range (-40°C to 150°C vs. -20°C to 115°C), offering improved performance margins in demanding thermal environments. Power delivery capability is comparable (125W vs. 120W).

The primary design consideration is the switching frequency differential: the TOP246YN operates at 66kHz to 132kHz compared to the STR-Y6735's 18.4kHz to 24.4kHz range. This higher frequency affects transformer design, EMI characteristics, and component selection in the power stage. Existing transformer designs optimized for the lower frequency range of the STR-Y6735 require re-evaluation for the TOP246YN.

Both devices are classified as not recommended for new designs or obsolete, respectively. For new applications, consultation of current-generation alternatives within each manufacturer's product line is advised.

Frequently Asked Questions (FAQ)

Q: Can the TOP246YN be used as a direct pin-for-pin replacement for the STR-Y6735?

A: Both devices use the TO-220-7 package with identical lead configuration, enabling direct mechanical substitution. However, the significantly different switching frequency (66kHz–132kHz vs. 18.4kHz–24.4kHz) requires transformer and filter component redesign. Electrical validation is mandatory before deployment.

Q: What are the key differences between these two parts?

A: The TOP246YN features higher breakdown voltage (700V vs. 500V), wider operating temperature range (-40°C to 150°C vs. -20°C to 115°C), and operates at a higher switching frequency. Power ratings are comparable. The TOP246YN includes frequency control capability, whereas the STR-Y6735 does not specify this feature.

Q: Are both parts RoHS compliant?

A: Yes, both the STR-Y6735 and TOP246YN are RoHS compliant with MSL rating of 1 (unlimited moisture sensitivity).

Q: Why is the switching frequency difference significant?

A: Switching frequency directly determines transformer core size, winding turns ratio, and filter component values. The TOP246YN's higher frequency allows smaller transformer designs but requires re-optimization of the entire power stage. Existing PCB layouts and component selections designed for 18.4kHz–24.4kHz operation are not directly compatible with 66kHz–132kHz operation.

Q: What is the product status implication for both parts?

A: The STR-Y6735 is classified as obsolete, indicating end-of-life status. The TOP246YN is marked "Not For New Designs," indicating limited availability and manufacturer recommendation against new application development. Both statuses indicate these are legacy components suitable for maintenance and repair of existing systems only.

Q: Are there differences in fault protection between these parts?

A: Both devices provide current limiting, over-temperature, and over-voltage protection. The STR-Y6735 additionally specifies over-load protection. Functional equivalence in protection capability is maintained for critical safety functions.