VSMS3700-GS18 Equivalent & Substitute Parts

Part Overview

The VSMS3700-GS18 is an infrared (IR) emitter operating at 950nm wavelength with a maximum forward current of 100mA and typical forward voltage of 1.3V. This component is packaged in a 2-PLCC surface mount configuration and is designed for applications requiring near-infrared emission in the 950nm spectrum. The part is currently listed as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity.

Substiute Parts

VSMS3700-GS18

Vishay Semiconductor Opto DivisionIn Stock: 932VSMS3700-GS18 Datasheet

Current PartRFQ

OPR2800T

TT Electronics/Optek TechnologyIn Stock: 2051OPR2800T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the VSMS3700-GS18 is determined by the following critical parameters:

Wavelength Compatibility: The substitute part OPR2800T operates at 875nm, which differs from the primary 950nm specification of the VSMS3700-GS18. This wavelength shift represents a functional difference in the infrared spectrum and must be evaluated against application-specific requirements.

Current Rating: The VSMS3700-GS18 supports a maximum forward current of 100mA, while the OPR2800T is rated for 50mA maximum. This represents a 50% reduction in current capacity.

Forward Voltage: The VSMS3700-GS18 has a typical forward voltage of 1.3V, compared to the OPR2800T maximum of 1.5V.

Radiant Intensity: The VSMS3700-GS18 provides 1.6mW/sr @ 100mA, while the OPR2800T provides 0.2mW/cm² @ 20mA. These measurements use different units and operating conditions, making direct comparison dependent on application geometry.

Viewing Angle: The VSMS3700-GS18 offers a 120° viewing angle versus the OPR2800T at 100°.

Package Configuration: The VSMS3700-GS18 uses a 2-PLCC package, while the OPR2800T uses a 4-SMD, No Lead Exposed Pad configuration. This represents a significant physical and electrical interface change.

Operating Temperature: The VSMS3700-GS18 operates from -40°C to 85°C, while the OPR2800T extends to 100°C maximum.

Parameter Comparison

Engineering Selection Recommendations

The OPR2800T is listed as an active product from TT Electronics/Optek Technology, providing ongoing availability and manufacturing support compared to the obsolete VSMS3700-GS18. Both components maintain ROHS3 compliance and are classified under the same HTSUS code (8541.41.0000), indicating equivalent regulatory and trade classification status.

The OPR2800T extends the maximum operating temperature to 100°C, providing a wider thermal operating window than the VSMS3700-GS18. However, the substitute part operates at a reduced maximum forward current (50mA versus 100mA) and a different wavelength (875nm versus 950nm). The package transition from 2-PLCC to 4-SMD, No Lead Exposed Pad requires PCB layout and assembly process modifications.

Selection of the OPR2800T as a substitute requires confirmation that the 875nm wavelength is compatible with the application's optical receiver or detection system, and that the reduced current rating and modified package footprint are acceptable for the intended circuit design.

Frequently Asked Questions (FAQ)

Q: Can the OPR2800T directly replace the VSMS3700-GS18 without circuit modifications?

A: No. The OPR2800T differs in wavelength (875nm vs. 950nm), maximum forward current (50mA vs. 100mA), forward voltage (1.5V max vs. 1.3V typ), and package configuration (4-SMD vs. 2-PLCC). Circuit redesign and PCB layout changes are required.

Q: What is the primary reason for substitution?

A: The VSMS3700-GS18 is obsolete. The OPR2800T is an active product with ongoing manufacturer support and availability.

Q: Does the wavelength difference affect compatibility?

A: Yes. The 75nm wavelength shift from 950nm to 875nm may affect optical coupling efficiency and receiver sensitivity depending on the application's photodetector spectral response characteristics.

Q: Are both parts RoHS compliant?

A: Yes. Both the VSMS3700-GS18 and OPR2800T are ROHS3 compliant.

Q: What are the package differences?

A: The VSMS3700-GS18 uses a 2-PLCC (Plastic Leaded Chip Carrier) package, while the OPR2800T uses a 4-SMD (Surface Mount Device) configuration with no lead exposed pad. These require different PCB footprints and assembly processes.

Q: How do the current ratings compare?

A: The VSMS3700-GS18 supports 100mA maximum forward current, while the OPR2800T is rated for 50mA. Applications requiring higher current operation cannot use the OPR2800T without circuit modification.

Q: What is the moisture sensitivity difference?

A: The VSMS3700-GS18 has MSL 2A (4 weeks shelf life in controlled humidity), while the OPR2800T has MSL 4 (72 hours). The OPR2800T requires more stringent moisture control during storage and handling.