ISP621-1 Equivalent & Substitute Parts

Part Overview

The ISP621-1 is an optoisolator with transistor output, single channel configuration in 4-DIP package. It provides 5300Vrms isolation voltage with DC input and transistor output topology. The part is Active status and widely used in industrial isolation applications requiring high voltage isolation with moderate output current capability. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are confirmed across critical parameters.

Substiute Parts

ISP621-1

Isocom Components 2004 LTDIn Stock: 1690ISP621-1 Datasheet

Current PartRFQ

ISP621-1X

Isocom Components 2004 LTDIn Stock: 45389ISP621-1X Datasheet

Parametric EquivalentRFQ

SFH615AA

Vishay Semiconductor Opto DivisionIn Stock: 4262SFH615AA Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the ISP621-1 are classified based on the following critical parameters that determine functional and mechanical compatibility:

Parametric Equivalent (ISP621-1X): Identical across all electrical specifications including isolation voltage (5300Vrms), current transfer ratio range (100%-600% @ 5mA), output voltage maximum (55V), output current (50mA), and package configuration (4-DIP). This part is a direct functional equivalent with identical performance envelope.

Similar Substitute (SFH615AA): Maintains compatibility in isolation voltage (5300Vrms), output current (50mA), package type (4-DIP), and mounting configuration (Through Hole). Differences exist in current transfer ratio minimum (50% vs 100%), output voltage maximum (70V vs 55V), and operating temperature range (-55°C to 100°C vs -30°C to 100°C). These differences represent relaxed or enhanced specifications that do not prevent substitution in applications designed for ISP621-1 parameters.

Parameter Comparison

Engineering Selection Recommendations

ISP621-1X is the primary substitute option. It maintains identical electrical specifications and package configuration, ensuring direct compatibility without design modification. Both parts are Active status with ROHS3 compliance and REACH unaffected designation.

SFH615AA is a secondary substitute option suitable for applications where the relaxed current transfer ratio minimum (50% vs 100%) and enhanced output voltage rating (70V vs 55V) do not conflict with circuit design requirements. The extended operating temperature range (-55°C to 100°C) provides additional thermal margin. This part is also Active status with equivalent compliance certifications.

Selection between ISP621-1X and SFH615AA depends on application-specific requirements for current transfer ratio performance and output voltage headroom. Both maintain the critical 5300Vrms isolation voltage, 4-DIP package footprint, and 50mA output current specification.

Frequently Asked Questions (FAQ)

Q: Can ISP621-1X be used as a direct replacement for ISP621-1? A: Yes. ISP621-1X is parametrically equivalent across all electrical and mechanical specifications, including isolation voltage, current transfer ratio range, output ratings, and 4-DIP package configuration.

Q: What are the key differences between ISP621-1 and SFH615AA? A: The primary differences are current transfer ratio minimum (100% vs 50% @ 5mA), maximum output voltage (55V vs 70V), and operating temperature range (-30°C to 100°C vs -55°C to 100°C). Isolation voltage, output current, package type, and saturation voltage are identical.

Q: Is SFH615AA compatible with ISP621-1 circuit designs? A: SFH615AA is mechanically and functionally compatible when the application does not require the ISP621-1's minimum current transfer ratio of 100% or when the lower minimum of 50% is acceptable. The enhanced output voltage rating provides additional design margin.

Q: Are all three parts in the same package? A: Yes. ISP621-1, ISP621-1X, and SFH615AA all use 4-DIP (0.300", 7.62mm) through-hole package configuration with identical pinout compatibility.

Q: What compliance certifications apply to these parts? A: All three parts are ROHS3 compliant, REACH unaffected, and carry EAR99 ECCN classification with HTSUS code 8541.49.8000.