FSFR1800 Equivalent & Substitute Parts

Part Overview

The FSFR1800 is an offline switching half-bridge power management IC manufactured by onsemi, designed for isolated converter applications with topology support up to 300kHz switching frequency. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The FSFR1800 delivers 260W power capacity with integrated fault protection including current limiting, overload, overvoltage, and overtemperature monitoring.

Substiute Parts

FSFR1800

onsemiIn Stock: 1825FSFR1800 Datasheet

Current PartRFQ

FSFR1800XS

onsemiIn Stock: 6489FSFR1800XS Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FSFR1800 is determined by strict alignment with the following critical parameters:

Core Electrical Requirements:

• Topology: Half-Bridge configuration
• Voltage - Breakdown: 500V minimum
• Voltage - Supply range: Must accommodate 11.3V ~ 25V operation
• Frequency - Switching: Up to 300kHz capability
• Power capacity: 260W minimum
• Output Isolation: Isolated topology
• Internal Switches: Integrated switching elements required

Mechanical & Environmental Requirements:

• Package / Case: 10-SIP Module, 9 Leads, Formed Leads
• Mounting Type: Through Hole
• Operating Temperature: -40°C ~ 130°C (TJ) minimum range

Compliance Requirements:

• RoHS Status: ROHS3 Compliant
• REACH Status: REACH Unaffected

The FSFR1800XS qualifies as a direct substitute based on matching topology, voltage ratings, switching frequency, power capacity, package configuration, and compliance certifications. Minor variations in startup voltage (12.5V vs 14.5V) and control features remain within acceptable substitution parameters for this product category.

Parameter Comparison

Engineering Selection Recommendations

The FSFR1800XS is the primary equivalent substitute for the FSFR1800. Both components share identical topology, voltage breakdown rating, switching frequency capability, power capacity, package configuration, and thermal operating range. Both maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for current production environments.

The FSFR1800XS operates with a lower startup voltage (12.5V versus 14.5V), which expands the operational envelope for low-voltage supply scenarios. The supply voltage range of the FSFR1800XS (10V ~ 25V) encompasses the FSFR1800 range (11.3V ~ 25V), providing broader compatibility.

Both components are classified as obsolete products. Selection between these parts should be based on inventory availability, packaging format (tube for FSFR1800XS), and specific application startup voltage requirements.

Frequently Asked Questions (FAQ)

Q: Can FSFR1800XS directly replace FSFR1800 in existing designs?

A: Yes. The FSFR1800XS maintains identical topology, voltage breakdown, switching frequency, power capacity, package configuration, and thermal range. The lower startup voltage of FSFR1800XS (12.5V) is compatible with applications designed for FSFR1800 (14.5V startup).

Q: What are the key differences between FSFR1800 and FSFR1800XS?

A: The primary differences are startup voltage (12.5V vs 14.5V), supply voltage range (10V ~ 25V vs 11.3V ~ 25V), and packaging format (tube for FSFR1800XS). The FSFR1800XS omits overload protection from its fault protection feature set, while maintaining current limiting, overvoltage, and overtemperature protection.

Q: Are both parts suitable for new designs?

A: Both FSFR1800 and FSFR1800XS are classified as obsolete. For new designs, evaluate long-term availability and consider alternative current-generation power management ICs from onsemi's active product portfolio.

Q: What packaging options are available?

A: FSFR1800 is supplied in standard packaging format. FSFR1800XS is supplied in tube packaging. Both use 10-SIP Module, 9 Leads, Formed Leads configuration with through-hole mounting.

Q: Do both parts meet current compliance requirements?

A: Yes. Both FSFR1800 and FSFR1800XS are ROHS3 compliant and REACH unaffected, meeting current regulatory standards for electronic component manufacturing and distribution.