SLR-37YY3F Yellow LED 3mm T-1 Through Hole Equivalent & Substitute Parts

Part Overview

The SLR-37YY3F is a yellow diffused 3mm T-1 through-hole LED manufactured by Rohm Semiconductor, designed for yellow indication applications in discrete electronic circuits. This part operates at a forward voltage of 2.1V with a test current of 10mA and delivers 16mcd luminous intensity at a 55° viewing angle. The product is currently obsolete, making identification of functionally equivalent substitute components essential for ongoing design support, maintenance, and production continuity.

Substiute Parts

SLR-37YY3F

Rohm SemiconductorIn Stock: 1210SLR-37YY3F Datasheet

Current PartRFQ

SSL-LX305D4YD

Lumex Opto/Components Inc.In Stock: 1079SSL-LX305D4YD Datasheet

SimilarRFQ

WP132XYT

KingbrightIn Stock: 1049WP132XYT Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SLR-37YY3F are qualified based on the following critical parameters:

• Color: Yellow
• Lens Size: 3mm, T-1
• Mounting Type: Through Hole
• Voltage - Forward (Vf): 2.1V
• Package / Case: Radial
• Wavelength - Peak: 585nm (±5nm tolerance acceptable)
• RoHS Status: ROHS3 Compliant

The identified substitute parts maintain compatibility across these core electrical and mechanical specifications. Variations in millicandela rating, viewing angle, and test current are acceptable within the scope of yellow LED indication applications, provided the forward voltage and physical form factor remain consistent.

Parameter Comparison

Engineering Selection Recommendations

Both identified substitute parts maintain active product status and full ROHS3 compliance, providing long-term availability and regulatory alignment superior to the obsolete SLR-37YY3F.

The SSL-LX305D4YD (Lumex Opto/Components Inc.) preserves the diffused lens transparency of the original part, making it the preferred substitute for applications where light diffusion characteristics are critical to system performance. This part operates at identical forward voltage (2.1V) and peak wavelength (585nm), with marginally lower millicandela output (15mcd versus 16mcd) and slightly wider viewing angle (60° versus 55°).

The WP132XYT (Kingbright) offers higher luminous intensity (20mcd) with a clear lens transparency, suitable for applications requiring increased brightness or where lens clarity is advantageous. Peak wavelength deviation (590nm versus 585nm) remains within acceptable yellow LED specification ranges. This part is available in bulk packaging.

Both substitutes accommodate the higher test current specification (20mA versus 10mA), which reflects modern LED design practices and does not preclude use in circuits originally designed for the SLR-37YY3F.

Frequently Asked Questions (FAQ)

Q: Can the SSL-LX305D4YD directly replace the SLR-37YY3F in existing PCB designs?

A: Yes. Both parts share identical 3mm T-1 radial package geometry, forward voltage (2.1V), and peak wavelength (585nm). PCB footprints and circuit connections require no modification. The diffused lens transparency is preserved, maintaining original light distribution characteristics.

Q: What is the primary difference between the SSL-LX305D4YD and WP132XYT substitutes?

A: The SSL-LX305D4YD maintains diffused lens transparency matching the original SLR-37YY3F, while the WP132XYT features a clear lens with higher luminous intensity (20mcd). Lens transparency selection depends on application requirements for light diffusion versus brightness.

Q: Are there compatibility concerns with the increased test current specification in substitute parts?

A: No. The substitute parts operate at 20mA test current versus the original 10mA specification. This reflects standard LED characterization practices and does not affect circuit compatibility. Existing current-limiting resistor calculations based on 2.1V forward voltage remain valid.

Q: Do the substitute parts meet the same regulatory and compliance standards as the original?

A: Yes. Both SSL-LX305D4YD and WP132XYT are ROHS3 compliant with REACH unaffected status, matching the original SLR-37YY3F compliance profile. Both parts carry EAR99 ECCN classification and identical HTSUS tariff codes.

Q: What is the significance of the peak wavelength variation in the WP132XYT (590nm versus 585nm)?

A: The 5nm wavelength difference falls within standard yellow LED specification tolerances and produces no perceptible color shift in indication applications. Both wavelengths are classified as yellow in the visible spectrum and are functionally equivalent for visual indication purposes.

Q: Can circuit designs accommodate both substitute parts interchangeably?

A: Yes. Both substitutes maintain the critical electrical parameters (2.1V forward voltage, radial through-hole package) and regulatory compliance required for direct substitution. Component selection between the two depends on specific application requirements for lens transparency and luminous intensity.