CNY172FM Equivalent & Substitute Parts

Part Overview

The CNY172FM is an optoisolator transistor with base output manufactured by onsemi, designed for high-voltage isolation applications requiring 7500Vpk isolation rating. This component features a single channel with transistor output and integrated base connection, housed in a 6-SMD surface mount package. The product is currently obsolete, making identification of compatible substitute parts essential for ongoing system support and new design implementations.

Substiute Parts

CNY172FM

onsemiIn Stock: 1083CNY172FM Datasheet

Current PartRFQ

CNY172SM

Fairchild SemiconductorIn Stock: 12768CNY172SM Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the CNY172FM is determined by the following critical parameters:

• Isolation Voltage: Minimum 7500Vpk or equivalent rms rating
• Number of Channels: Single channel configuration
• Output Configuration: Transistor with base output
• Current Transfer Ratio: 63% minimum at 10mA input
• Maximum Output Voltage: 70V capability
• Maximum Output Current: 50mA per channel
• Package Type: 6-SMD, Gull Wing surface mount
• Operating Temperature Range: -40°C to 100°C
• Vce Saturation: 400mV maximum

The CNY172SM meets these substitution criteria with compatible electrical and mechanical specifications, though with a lower isolation voltage rating of 4170Vrms.

Parameter Comparison

Engineering Selection Recommendations

The CNY172SM from Fairchild Semiconductor is the identified substitute for the obsolete CNY172FM. Both components share identical electrical performance characteristics including current transfer ratio, output voltage and current ratings, and operating temperature range. The primary distinction is the isolation voltage specification: the CNY172FM provides 7500Vpk isolation while the CNY172SM provides 4170Vrms isolation.

Selection between these parts depends on the specific isolation voltage requirement of the application. For applications requiring 7500Vpk isolation, the CNY172FM specification must be maintained. For applications with lower isolation voltage requirements, the CNY172SM provides an active product alternative with full electrical compatibility.

Both components carry identical compliance certifications (ECCN: EAR99, HTSUS: 8541.49.8000) and are suitable for surface mount assembly in 6-SMD Gull Wing packages.

Frequently Asked Questions (FAQ)

Q: Can CNY172SM directly replace CNY172FM in all applications?

A: Direct replacement is possible only if the application isolation voltage requirement does not exceed 4170Vrms. The CNY172SM has a lower isolation voltage rating than the CNY172FM. Applications requiring 7500Vpk isolation must use the CNY172FM specification or identify alternative components with equivalent isolation ratings.

Q: Are the package dimensions identical between CNY172FM and CNY172SM?

A: Both components use 6-SMD Gull Wing surface mount packages. Mechanical compatibility is confirmed for PCB assembly and reflow soldering processes.

Q: What is the difference between Vpk and Vrms isolation ratings?

A: Vpk (peak voltage) and Vrms (root mean square voltage) are different measurement standards for isolation voltage. The CNY172FM specifies 7500Vpk while the CNY172SM specifies 4170Vrms. These represent different isolation voltage test conditions and cannot be directly compared without conversion factors specific to the test methodology.

Q: Is the CNY172SM currently available?

A: Yes, the CNY172SM is listed as Active product status with 12,750 pieces in stock. The CNY172FM is obsolete with limited remaining inventory.

Q: Are the electrical performance characteristics identical?

A: Yes. Current transfer ratio, output voltage and current ratings, switching times, saturation voltage, and operating temperature range are identical between both components.

Q: What compliance certifications apply to these components?

A: Both the CNY172FM and CNY172SM carry ECCN: EAR99 and HTSUS: 8541.49.8000 classifications. Both are REACH Unaffected.