1SS355-7 Equivalent & Substitute Parts

Part Overview

The 1SS355-7 is a general-purpose rectifier diode manufactured by Diodes Incorporated, designed for surface mount applications in the SOD-323 package. This component operates at a maximum reverse voltage of 80 V with an average rectified current rating of 100 mA and a forward voltage drop of 1.2 V at 100 mA. The part is classified as obsolete, which necessitates identification of active equivalent components for new designs and ongoing production requirements. Substitute parts must maintain electrical compatibility while offering improved availability and active product status.

Substiute Parts

1SS355-7

Diodes IncorporatedIn Stock: 11711SS355-7 Datasheet

Current PartRFQ

1N4448HWS-7-F

Diodes IncorporatedIn Stock: 1272071N4448HWS-7-F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1SS355-7 is determined by the following critical electrical and mechanical parameters:

Voltage Rating Compatibility: The substitute part must maintain a maximum reverse voltage (Vr) of 80 V or greater to ensure safe operation in the original circuit application.

Package Compatibility: The substitute part must use the SOD-323 surface mount package to ensure mechanical and thermal compatibility with existing PCB layouts and assembly processes.

Current Rating: The substitute part must support the required average rectified current (Io) of 100 mA or greater. Parts with higher current ratings remain compatible as they operate within the original circuit's current demands.

Forward Voltage Characteristics: The substitute part's forward voltage drop must be within acceptable circuit operating parameters. Variations in forward voltage do not preclude substitution provided the voltage remains within typical rectifier diode specifications.

Reverse Recovery Time: The substitute part must maintain fast recovery characteristics (trr ≤ 4 ns) to preserve circuit switching performance.

Compliance Requirements: The substitute part must maintain ROHS3 compliance and REACH unaffected status to satisfy regulatory and supply chain requirements.

The 1N4448HWS-7-F meets all substitution criteria while offering active product status and improved current handling capability.

Parameter Comparison

Engineering Selection Recommendations

The 1N4448HWS-7-F is the qualified substitute for the obsolete 1SS355-7 based on the following engineering criteria:

Electrical Equivalence: Both components share identical maximum reverse voltage (80 V), reverse recovery time (4 ns), and reverse leakage current (100 nA @ 80 V) specifications. The substitute's higher current rating (250 mA versus 100 mA) provides additional design margin without compromising circuit performance.

Package Compatibility: Both parts utilize the SOD-323 surface mount package, ensuring direct mechanical and thermal compatibility with existing PCB designs and assembly equipment.

Regulatory Compliance: The 1N4448HWS-7-F maintains ROHS3 compliance and REACH unaffected status, satisfying supply chain and environmental regulatory requirements equivalent to the original part.

Product Availability: The 1N4448HWS-7-F holds active product status with substantial inventory availability (127,190 pieces), ensuring reliable long-term supply compared to the obsolete 1SS355-7.

Temperature Operating Range: The substitute provides an extended operating temperature range (-65°C to 150°C) compared to the main part's junction temperature maximum of 150°C, offering improved thermal performance margin.

Frequently Asked Questions (FAQ)

Q: Can the 1N4448HWS-7-F directly replace the 1SS355-7 in existing designs?

A: Yes. Both components share identical reverse voltage (80 V), reverse recovery time (4 ns), and package specifications (SOD-323). The substitute's higher current rating (250 mA) operates within the original circuit's 100 mA requirement without performance degradation.

Q: What is the primary reason for substitution?

A: The 1SS355-7 is classified as obsolete. The 1N4448HWS-7-F is an active equivalent component from the same manufacturer, ensuring continued availability and supply chain reliability.

Q: Are there differences in forward voltage characteristics?

A: The 1N4448HWS-7-F exhibits a forward voltage of 1.25 V at 150 mA compared to the 1SS355-7's 1.2 V at 100 mA. This 0.05 V difference remains within acceptable rectifier diode operating parameters and does not affect circuit functionality.

Q: Does the substitute require PCB layout modifications?

A: No. Both components use the identical SOD-323 surface mount package (SC-76), enabling direct PCB footprint compatibility without layout changes.

Q: What is the significance of the higher current rating on the substitute?

A: The 1N4448HWS-7-F's 250 mA rating provides additional design margin for the original 100 mA application. This higher rating does not introduce compatibility issues and improves component reliability under load.

Q: Are compliance certifications maintained with the substitute?

A: Yes. The 1N4448HWS-7-F maintains ROHS3 compliance and REACH unaffected status, matching the regulatory certifications of the original 1SS355-7.

Q: What packaging format is available for the substitute?

A: The 1N4448HWS-7-F is supplied in Tape & Reel (TR) format, suitable for automated assembly processes. The original 1SS355-7 packaging format was not specified in the available data.