SFH617A-1 Equivalent & Substitute Parts

Part Overview

The SFH617A-1 is an optoisolator with transistor output manufactured by Vishay Semiconductor Opto Division. This 4-DIP through-hole component provides 5300Vrms isolation with a single channel and 50mA output current capability. The part is active and in production with 2083 units currently in stock. Equivalent and substitute parts are necessary when the primary part is unavailable, when design flexibility is required across manufacturing sources, or when alternative current transfer ratio specifications better match application requirements.

Substiute Parts

SFH617A-1

Vishay Semiconductor Opto DivisionIn Stock: 2178SFH617A-1 Datasheet

Current PartRFQ

FOD817

onsemiIn Stock: 18140FOD817 Datasheet

MFR RecommendedRFQ

FOD817A

onsemiIn Stock: 20361FOD817A Datasheet

MFR RecommendedRFQ

FOD817B

onsemiIn Stock: 9764FOD817B Datasheet

MFR RecommendedRFQ

FOD817C

onsemiIn Stock: 18744FOD817C Datasheet

MFR RecommendedRFQ

FOD817D

onsemiIn Stock: 1943FOD817D Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SFH617A-1 is determined by the following critical parameters that must remain compatible:

Mandatory Compatibility Parameters:

• Package / Case: 4-DIP (0.300", 7.62mm) — ensures mechanical and electrical pin compatibility
• Mounting Type: Through Hole — maintains PCB assembly compatibility
• Number of Channels: 1 — preserves circuit topology
• Voltage - Output (Max): 70V — ensures output voltage rating compatibility
• Current - Output / Channel: 50mA — maintains output current capability
• Operating Temperature: -55°C ~ 110°C — ensures thermal operating range compatibility
• Input Type: DC — maintains input signal compatibility
• Output Type: Transistor — preserves output stage architecture

Substitution-Determining Parameters:

• Voltage - Isolation: Substitute parts must meet or exceed 5300Vrms isolation requirement
• Current Transfer Ratio: Substitute parts must fall within or above the 40%-80% @ 10mA range to ensure adequate signal transfer
• Vce Saturation: Lower values indicate improved performance; substitute parts with ≤400mV are acceptable
• Compliance: RoHS3 and REACH Unaffected status required

The FOD817 series from onsemi meets all mandatory compatibility requirements. All variants (FOD817, FOD817A, FOD817B, FOD817C, FOD817D) are pin-compatible 4-DIP optoisolators with identical mechanical and electrical interfaces. Variants differ only in current transfer ratio specifications, allowing selection based on application gain requirements.

Parameter Comparison

Engineering Selection Recommendations

All FOD817 series variants are direct mechanical and electrical substitutes for the SFH617A-1. Selection among FOD817, FOD817A, FOD817B, FOD817C, and FOD817D depends on application current transfer ratio requirements:

FOD817: Minimum 50% CTR @ 5mA. Suitable for applications requiring moderate gain with wide tolerance band (50%-600%).

FOD817A: Minimum 80% CTR @ 5mA. Appropriate for applications requiring higher minimum gain with narrower tolerance (80%-160%).

FOD817B: Minimum 130% CTR @ 5mA. Suitable for applications requiring elevated gain specifications (130%-260%).

FOD817C: Minimum 200% CTR @ 5mA. Appropriate for high-gain applications (200%-400%).

FOD817D: Minimum 300% CTR @ 5mA. Suitable for maximum gain applications (300%-600%).

All substitute parts maintain active product status, ROHS3 compliance, and REACH Unaffected designation. The FOD817 series offers improved Vce saturation (200mV maximum versus 400mV) and lower forward voltage (1.2V typical versus 1.35V), providing enhanced performance characteristics. Isolation voltage is 5000Vrms, which is 300Vrms lower than the SFH617A-1; applications requiring 5300Vrms isolation must retain the original part.

Frequently Asked Questions (FAQ)

Q: Are FOD817 series parts pin-compatible with SFH617A-1?

A: Yes. All FOD817 variants use identical 4-DIP (0.300", 7.62mm) through-hole packaging with the same pin configuration. Direct socket substitution is possible without PCB modification.

Q: What is the primary difference between FOD817 variants?

A: Current transfer ratio (CTR) specifications differ among variants. FOD817 ranges 50%-600%, FOD817A ranges 80%-160%, FOD817B ranges 130%-260%, FOD817C ranges 200%-400%, and FOD817D ranges 300%-600%. All other electrical and mechanical parameters are identical.

Q: Can I substitute FOD817 for SFH617A-1 in all applications?

A: FOD817 series parts are suitable for applications where 5000Vrms isolation is sufficient. Applications specifically requiring 5300Vrms isolation must use the SFH617A-1 or equivalent parts rated for 5300Vrms or higher.

Q: How do current transfer ratio specifications affect circuit design?

A: CTR determines the output current relative to input current. Higher CTR variants (FOD817C, FOD817D) provide greater output signal with lower input drive requirements. Lower CTR variants (FOD817, FOD817A) require higher input current to achieve equivalent output. Circuit design must account for the selected variant's CTR range.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. SFH617A-1 and all FOD817 series variants are ROHS3 Compliant and REACH Unaffected, meeting current environmental and regulatory requirements.

Q: What is the inventory status of substitute parts?

A: FOD817 (18,111 units), FOD817A (20,300 units), FOD817B (9,674 units), FOD817C (18,671 units), and FOD817D (1,840 units) are in stock. SFH617A-1 has 2,083 units available.