LTL-3211A Equivalent & Substitute Parts

Part Overview

The LTL-3211A is a red diffused through-hole LED manufactured by Lite-On Inc., designed for indication applications with a dominant wavelength of 657nm and forward voltage of 2.1V at 20mA test current. This part is classified as obsolete, necessitating identification of active equivalent alternatives for new designs and ongoing production requirements. Substitute parts must maintain compatibility across mechanical mounting, optical characteristics, and electrical performance parameters.

Substiute Parts

LTL-3211A

Lite-On Inc.In Stock: 759LTL-3211A Datasheet

Current PartRFQ

LTL-433HR

Lite-On Inc.In Stock: 948LTL-433HR Datasheet

MFR RecommendedRFQ

LTL-433P

Lite-On Inc.In Stock: 801LTL-433P Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LTL-3211A are identified based on the following allowable parameter tolerances:

Mechanical Compatibility: Mounting type (through hole), lens style (rectangle with flat top), and lens size (5.00mm x 2.00mm) must remain constant. Height variation is permitted within design constraints.

Optical Compatibility: Color (red) and lens transparency (diffused) are fixed requirements. Wavelength-dominant must remain within the red spectrum (620–660nm range). Viewing angle of 140° is maintained across substitutes.

Electrical Compatibility: Forward voltage (Vf) tolerance of ±0.1V and test current of 10–20mA are acceptable. Millicandela rating may vary based on application requirements.

Regulatory Compliance: Moisture sensitivity level, ECCN, and HTSUS classifications are provided for reference but do not restrict substitution eligibility.

Parameter Comparison

Engineering Selection Recommendations

LTL-433P (Parametric Equivalent): This part provides the closest electrical and optical match to the LTL-3211A, maintaining identical forward voltage (2.1V) and dominant wavelength (657nm). Both parts deliver 1.1mcd brightness. The LTL-433P is active and ROHS3 compliant, making it the primary substitute for direct replacement in new designs. Height increases from 7.00mm to 7.50mm; verify PCB layout clearance before implementation. Moisture sensitivity level changes from MSL 1 to MSL 2A; storage conditions must accommodate 4-week shelf life limits.

LTL-433HR (MFR Recommended): This part is designated as the manufacturer-recommended substitute and carries active product status with ROHS3 compliance and unlimited moisture sensitivity (MSL 1). The dominant wavelength shifts to 623nm (orange-red spectrum), representing a perceptible color shift from the original 657nm red. Forward voltage decreases to 2.0V, and brightness increases to 3.7mcd at reduced test current (10mA). This substitute is suitable for applications where wavelength variation is acceptable and increased brightness is beneficial. Height increases to 7.50mm.

Both substitutes maintain mechanical compatibility through identical lens size (5.00mm x 2.00mm), lens style (rectangle with flat top), and viewing angle (140°). Selection depends on wavelength tolerance and brightness requirements of the target application.

Frequently Asked Questions (FAQ)

Q: Can LTL-433HR be used as a direct replacement for LTL-3211A?

A: LTL-433HR is mechanically and electrically compatible but introduces a wavelength shift from 657nm to 623nm. This results in a visible color change from pure red to orange-red. Use this substitute only if the application tolerates wavelength variation and benefits from increased brightness (3.7mcd vs. 1.1mcd).

Q: Which substitute maintains the closest optical match to LTL-3211A?

A: LTL-433P maintains identical dominant wavelength (657nm) and brightness (1.1mcd), providing the closest optical performance match. Forward voltage remains 2.1V, ensuring minimal circuit redesign.

Q: What is the impact of height increase from 7.00mm to 7.50mm?

A: Both substitutes increase maximum height by 0.50mm. Verify that PCB layout, component clearances, and mechanical enclosure accommodate this dimension change before board redesign.

Q: How does the moisture sensitivity level change affect storage and handling?

A: LTL-3211A and LTL-433HR both carry MSL 1 (unlimited shelf life). LTL-433P carries MSL 2A, requiring storage at controlled humidity and limiting shelf life to 4 weeks after packaging. Implement appropriate moisture control procedures and track component age for LTL-433P inventory.

Q: Are both substitutes RoHS compliant?

A: Yes. LTL-433HR and LTL-433P are both ROHS3 compliant. The original LTL-3211A does not specify RoHS status.

Q: What is the difference between test current specifications?

A: LTL-3211A operates at 20mA test current, while both substitutes operate at 10mA. This reduction in test current may affect brightness perception in specific circuit configurations. Verify that circuit current-limiting resistors accommodate the lower test current specification.