FSFR1700USL Equivalent & Substitute Parts

Part Overview

The FSFR1700USL is an offline switching half-bridge power management IC manufactured by onsemi, designed for isolated converter applications with up to 300kHz switching frequency and 200W power handling capability. The device features integrated switches, comprehensive fault protection, and operates across -40°C to 130°C. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

FSFR1700USL

onsemiIn Stock: 2218FSFR1700USL Datasheet

Current PartRFQ

FSFR1700XSL

Fairchild SemiconductorIn Stock: 16531FSFR1700XSL Datasheet

DirectRFQ

FSFR1700XS

Fairchild SemiconductorIn Stock: 1584FSFR1700XS Datasheet

Parametric EquivalentRFQ

FSFR1800XS

onsemiIn Stock: 6489FSFR1800XS Datasheet

Parametric EquivalentRFQ

FSFR1800XSL

Fairchild SemiconductorIn Stock: 2665FSFR1800XSL Datasheet

Parametric EquivalentRFQ

FSFR2100XS

onsemiIn Stock: 32784FSFR2100XS Datasheet

Parametric EquivalentRFQ

FSFR2100XSL

onsemiIn Stock: 1219FSFR2100XSL Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the FSFR1700USL is determined by strict adherence to the following electrical and mechanical parameters:

Critical Matching Parameters:

• Topology: Half-Bridge
• Output Isolation: Isolated
• Voltage - Breakdown: 500V
• Voltage - Supply (Vcc/Vdd): 10V ~ 25V
• Duty Cycle: 50%
• Frequency - Switching: Up to 300kHz
• Fault Protection: Current Limiting, Over Temperature, Over Voltage
• Control Features: Frequency Control
• Operating Temperature: -40°C ~ 130°C (TJ)
• Package / Case: 10-SIP Module, 9 Leads, Formed Leads
• Mounting Type: Through Hole

Allowable Variation Parameters:

• Power (Watts): Equal or greater than 200W
• Manufacturer: Different manufacturers acceptable
• Product Status: Active or Obsolete
• Packaging: Different packaging types acceptable

Substitute parts must maintain all critical matching parameters while power rating may be equal or higher. Package variations are permitted provided the 9-lead SIP form factor and through-hole mounting are preserved.

Parameter Comparison

Engineering Selection Recommendations

Direct Substitutes (Highest Compatibility):

FSFR1700XSL and FSFR1700XS maintain identical electrical specifications and power ratings to the FSFR1700USL. FSFR1700XSL is manufactured by Fairchild Semiconductor with Active product status, providing long-term availability. FSFR1700XS is also Fairchild Semiconductor with Active status but uses a 10-SSIP package variant instead of 10-SIP (L forming). Both are suitable for direct replacement in applications where the FSFR1700USL was originally specified.

Higher Power Alternatives:

FSFR1800XS and FSFR2100XS provide increased power handling (260W and 400W respectively) while maintaining all critical electrical parameters. These are suitable for applications requiring higher power capacity within the same topology and control framework. FSFR1800XSL and FSFR2100XSL offer the same power ratings with formed leads packaging. FSFR2100XSL is manufactured by onsemi with Obsolete status.

Compliance Considerations:

FSFR1800XS and FSFR2100XS carry RoHS3 compliance certification. FSFR1700XSL and FSFR1800XSL are manufactured by Fairchild Semiconductor. All substitute parts maintain REACH Unaffected status and EAR99 export classification consistent with the original part.

Frequently Asked Questions (FAQ)

Q: Can FSFR1700XS replace FSFR1700USL directly?

A: FSFR1700XS is electrically equivalent with identical power rating and all critical parameters. The package variant is 10-SSIP instead of 10-SIP (L forming), which may require PCB layout verification for lead compatibility and spacing.

Q: What is the difference between FSFR1700XSL and FSFR1700XS?

A: Both are manufactured by Fairchild Semiconductor with Active product status. FSFR1700XSL uses 9-SIP (L forming) package with formed leads, while FSFR1700XS uses 9-SIP package without specified lead forming. FSFR1700XSL provides closer mechanical compatibility to the original FSFR1700USL.

Q: Can I use FSFR2100XS or FSFR2100XSL in place of FSFR1700USL?

A: Yes. FSFR2100XS and FSFR2100XSL maintain all critical electrical parameters and topology specifications. The 400W power rating exceeds the 200W requirement, making them suitable for applications where higher power capacity is acceptable or beneficial. Through-hole mounting and 9-lead SIP form factor are preserved.

Q: What is the advantage of FSFR1800XS over FSFR1700USL?

A: FSFR1800XS provides 260W power capacity compared to 200W, while maintaining identical electrical specifications, topology, and operating parameters. It carries RoHS3 compliance certification. Product status is Obsolete, consistent with the original part.

Q: Are there packaging differences I should consider?

A: All substitute parts maintain through-hole mounting and 9-lead SIP form factor. FSFR1700XSL and FSFR2100XSL specify 9-SIP (L forming) with formed leads, matching the original FSFR1700USL package. FSFR1700XS uses 10-SSIP variant. FSFR1800XS and FSFR2100XS use standard 9-SIP. PCB layout compatibility should be verified for package variants.

Q: Which substitute offers the best long-term availability?

A: FSFR1700XSL manufactured by Fairchild Semiconductor carries Active product status, indicating ongoing availability and support. FSFR1700XS also has Active status. Other substitutes are classified as Obsolete.