EFR5366X Equivalent & Substitute Parts Reference

Part Overview

The EFR5366X is a red LED indicator manufactured by Stanley Electric Co, designed for through-hole mounting in 5mm T-1 3/4 form factor applications. This component features a 626nm dominant wavelength with 3600mcd luminous intensity and operates at 1.9V forward voltage with 20mA test current.

The EFR5366X is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this LED indicator.

Substiute Parts

EFR5366X

Stanley Electric CoIn Stock: 833EFR5366X Datasheet

Current PartRFQ

333-2SDRT/S530-A3

Everlight Electronics Co LtdIn Stock: 1098333-2SDRT/S530-A3 Datasheet

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383-2SURC/S400-A6

Everlight Electronics Co LtdIn Stock: 687383-2SURC/S400-A6 Datasheet

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383-2SURC/S400-A8

Everlight Electronics Co LtdIn Stock: 851383-2SURC/S400-A8 Datasheet

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383-2SURC/S530-A3

Everlight Electronics Co LtdIn Stock: 758383-2SURC/S530-A3 Datasheet

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383-2SURC/S530-A4

Everlight Electronics Co LtdIn Stock: 830383-2SURC/S530-A4 Datasheet

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383-2SURC/S530-A5

Everlight Electronics Co LtdIn Stock: 980383-2SURC/S530-A5 Datasheet

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LTL353QRKNN

Lite-On Inc.In Stock: 768LTL353QRKNN Datasheet

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SLI-570UT3F

Rohm SemiconductorIn Stock: 24740SLI-570UT3F Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the EFR5366X is determined by strict alignment with the following critical parameters:

Primary Compatibility Criteria:

• Lens Size: 5mm, T-1 3/4 form factor
• Mounting Type: Through Hole with radial leads
• Color: Red wavelength range (620nm–640nm dominant wavelength acceptable)
• Lens Transparency: Clear
• Lens Style: Round with Domed Top
• Package / Case: Radial

Secondary Compatibility Criteria:

• Voltage - Forward (Vf): 1.9V–2.0V range
• Current - Test: 20mA
• Viewing Angle: 6°–20° range
• Millicandela Rating: 1250mcd minimum (brightness may vary based on application requirements)

Compliance Considerations:

• Product Status: Active status preferred for long-term availability
• RoHS Status: ROHS3 Compliant preferred
• ECCN and HTSUS codes must match for regulatory consistency

Substitute parts meeting these criteria are grouped by manufacturer and brightness rating to facilitate selection based on specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

Direct Substitutes (Matched Vf and Viewing Angle):

The LTL353QRKNN and SLI-570UT3F are the primary direct substitutes for the EFR5366X. Both components share the identical 1.9V forward voltage, 5mm T-1 3/4 form factor, and through-hole radial mounting configuration. These parts maintain electrical compatibility with existing circuit designs without requiring resistor recalculation.

• LTL353QRKNN (Lite-On Inc.): 4200mcd brightness, 12° viewing angle, 631nm dominant wavelength. Active product status with ROHS3 compliance. Suitable for applications requiring moderate brightness with wider viewing angle than the original.

• SLI-570UT3F (Rohm Semiconductor): 4000mcd brightness, 20° viewing angle, 630nm dominant wavelength. Active product status with ROHS3 compliance and highest inventory availability (24,707 pcs). Recommended for applications prioritizing supply chain continuity and wide-angle visibility.

Alternative Substitutes (2V Forward Voltage):

The Everlight Electronics 383-2SURC/S530 series (A3, A4, A5 variants) and 333-2SDRT/S530-A3 operate at 2V forward voltage, requiring circuit modification. These parts are suitable only when design flexibility permits resistor adjustment to accommodate the 0.1V voltage increase.

• 383-2SURC/S530-A5 (Everlight Electronics): 5000mcd brightness, 6° viewing angle, 624nm dominant wavelength. Highest brightness option among Everlight substitutes. Narrow viewing angle suitable for focused indication applications.

• 383-2SURC/S530-A4 (Everlight Electronics): 4000mcd brightness, 6° viewing angle. Moderate brightness with narrow viewing angle.

• 383-2SURC/S530-A3 (Everlight Electronics): 2500mcd brightness, 6° viewing angle. Lower brightness option for applications with reduced visibility requirements.

• 333-2SDRT/S530-A3 (Everlight Electronics): 1250mcd brightness, 10° viewing angle, 624nm dominant wavelength. Lowest brightness option; suitable only for applications with minimal visibility requirements.

Selection Criteria Summary:

1. For direct electrical compatibility without circuit modification: Select LTL353QRKNN or SLI-570UT3F (both 1.9V).

2. For maximum supply availability: Select SLI-570UT3F (24,707 pcs in stock).

3. For brightness matching or exceeding original specification: Select LTL353QRKNN (4200mcd), SLI-570UT3F (4000mcd), or 383-2SURC/S530-A5 (5000mcd, requires 2V circuit adjustment).

4. For narrow viewing angle applications: Select 383-2SURC/S530 series (6° viewing angle).

5. For wide viewing angle applications: Select SLI-570UT3F (20° viewing angle).

All recommended substitutes are active products with ROHS3 compliance, ensuring regulatory conformance and long-term availability.

Frequently Asked Questions (FAQ)

Q1: Can I use a 2V forward voltage LED as a direct replacement for the EFR5366X without circuit modification?

A: No. The EFR5366X operates at 1.9V forward voltage. Substitutes operating at 2V (Everlight 383-2SURC/S530 series and 333-2SDRT/S530-A3) require recalculation of the current-limiting resistor to maintain proper circuit operation. The resistor value must be adjusted to account for the 0.1V voltage difference. Direct substitution without modification will result in incorrect LED brightness and potential circuit malfunction.

Q2: What is the difference between the Everlight 383-2SURC/S530-A3, A4, and A5 variants?

A: These three variants differ only in millicandela rating (brightness): A3 provides 2500mcd, A4 provides 4000mcd, and A5 provides 5000mcd. All three share identical electrical parameters (2V forward voltage, 20mA test current), mechanical dimensions (5mm, T-1 3/4 form factor), and optical characteristics (624nm dominant wavelength, 6° viewing angle, clear lens). Selection depends on the brightness requirement of the specific application.

Q3: Why do some substitute parts have a "Colorless" lens while the EFR5366X has a "Red" lens?

A: Lens color refers to the physical tint of the lens material. A colorless lens transmits the red light emitted by the LED die without additional color filtering, while a red lens adds color filtering. Both configurations produce red light indication. The choice between colorless and red lens does not affect electrical compatibility; it is an optical design choice by the manufacturer. For visual consistency in applications where multiple LEDs are visible, verify that all selected parts use the same lens color specification.

Q4: Is the SLI-570UT3F suitable for applications requiring a narrow viewing angle?

A: No. The SLI-570UT3F has a 20° viewing angle, which is the widest among all listed substitutes. For applications requiring a narrow viewing angle (6°), select the Everlight 383-2SURC/S530 series (A3, A4, or A5). The original EFR5366X has a 10° viewing angle, which is intermediate between these options.

Q5: What is the significance of the "Product Status: Active" designation for substitute parts?

A: Active product status indicates that the manufacturer continues to produce and support the component. This ensures long-term availability, ongoing supply chain support, and manufacturer technical assistance. The EFR5366X is classified as obsolete, meaning Stanley Electric Co no longer manufactures this part. All recommended substitutes have active status, providing design continuity and supply security for future production runs.

Q6: Can I mix different substitute parts in the same circuit board design?

A: Mixing substitute parts with different forward voltages (1.9V vs. 2V) in the same circuit is not recommended without individual current-limiting resistors for each LED. If all LEDs in a design share a common current-limiting resistor, all LEDs must have identical forward voltage specifications. For designs using a single resistor per LED, different forward voltages are acceptable. Verify your circuit topology before selecting mixed substitutes.

Q7: Are all listed substitute parts ROHS3 compliant?

A: Yes. All substitute parts listed (LTL353QRKNN, SLI-570UT3F, and all Everlight variants) are ROHS3 compliant. The EFR5366X does not specify RoHS status. If your application requires RoHS compliance, all listed substitutes meet this requirement.

Q8: What is the maximum height difference between the EFR5366X and substitute parts?

A: The EFR5366X has a maximum height of 8.80mm. Substitute parts range from 8.80mm (LTL353QRKNN) to 8.90mm (Everlight variants) to 8.85mm (SLI-570UT3F). The maximum height difference is 0.10mm. This variation is within typical PCB assembly tolerances and does not affect mechanical compatibility with standard through-hole footprints.

Q9: Which substitute part has the highest inventory availability?

A: The SLI-570UT3F (Rohm Semiconductor) has the highest inventory availability with 24,707 pcs in stock. This significantly exceeds inventory levels of other substitutes, making it the preferred choice for applications prioritizing supply chain continuity and rapid procurement.

Q10: If I need to replace the EFR5366X in an existing design, which substitute requires the least circuit modification?

A: The LTL353QRKNN and SLI-570UT3F both operate at 1.9V forward voltage, matching the EFR5366X exactly. Either part can be substituted without circuit modification. The SLI-570UT3F is recommended due to superior inventory availability (24,707 pcs vs. 665 pcs for LTL353QRKNN).