MDA6940C 14-Segment Alphanumeric Display Module

Part Overview

The MDA6940C is a 2-character, 14-segment alphanumeric LED display module manufactured by onsemi. It features a red color output with common cathode configuration, designed for applications requiring alphanumeric character display capabilities. The product is classified as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity.

Substiute Parts

MDA6940C

onsemiIn Stock: 1085MDA6940C Datasheet

Current PartRFQ

LTP-3784E

Lite-On Inc.In Stock: 3093LTP-3784E Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MDA6940C is determined by the following critical parameters:

• Display Configuration: 2-character, 14-segment alphanumeric format
• Common Pin Type: Common cathode architecture
• Package Type: 18-DIP form factor
• Character Size: 0.54" (13.72mm) alphanumeric segments
• Electrical Specifications: Forward voltage 2V, test current 20mA
• Color Category: Red or red-spectrum output (635nm peak wavelength)

The LTP-3784E from Lite-On Inc. qualifies as a substitute based on matching all critical parameters. While the LTP-3784E exhibits orange-red color output (630nm peak wavelength) rather than pure red, this represents a minor spectral shift within acceptable red-spectrum display applications. The substitute maintains identical character count, display type, common cathode configuration, package format, and electrical operating parameters.

Parameter Comparison

Engineering Selection Recommendations

The LTP-3784E serves as the primary substitute for the obsolete MDA6940C. Selection should be based on the following factors:

Product Status: The LTP-3784E maintains active product status with current manufacturing support, whereas the MDA6940C is obsolete. This ensures long-term availability and supply chain continuity.

Compliance and Certifications: The LTP-3784E is RoHS3 compliant and REACH affected, providing regulatory alignment with current environmental standards. The MDA6940C carries REACH unaffected status, reflecting its obsolete classification.

Electrical Compatibility: Both components operate at identical forward voltage (2V) and test current (20mA), ensuring direct circuit compatibility without modification to drive electronics or current-limiting resistor networks.

Optical Characteristics: The LTP-3784E exhibits slightly lower millicandela rating (2.3mcd versus 4mcd) and a minor wavelength shift toward orange-red (630nm versus 635nm). These differences are within acceptable tolerances for standard alphanumeric display applications where precise color matching is not critical.

Mechanical Fit: Physical dimensions are nearly identical, with negligible differences in height and width. Both components use 18-DIP packaging, ensuring PCB footprint compatibility.

Frequently Asked Questions (FAQ)

Q: Can the LTP-3784E directly replace the MDA6940C without circuit modifications?

A: Yes. Both components share identical electrical specifications (2V forward voltage, 20mA test current), common cathode configuration, and 18-DIP package format. No modifications to drive circuitry or resistor networks are required.

Q: What is the significance of the color difference between red (635nm) and orange-red (630nm)?

A: The 5nm wavelength difference represents a minor shift within the red spectrum. For applications where precise color matching is not specified, this difference is imperceptible to the human eye and does not affect functional performance.

Q: Why is the millicandela rating lower for the LTP-3784E (2.3mcd versus 4mcd)?

A: The LTP-3784E produces lower luminous intensity. Applications requiring maximum brightness should evaluate whether 2.3mcd meets minimum visibility requirements. For standard display applications with adequate ambient lighting or close viewing distances, this reduction is typically acceptable.

Q: Are there any packaging or handling differences between these components?

A: The MDA6940C uses standard DIP packaging, while the LTP-3784E is supplied in tube packaging. Both maintain identical moisture sensitivity level (MSL 1, unlimited), requiring no special storage or handling precautions.

Q: What is the advantage of selecting the LTP-3784E over the MDA6940C?

A: The LTP-3784E is an active product with current manufacturing support and RoHS3 compliance, ensuring supply availability and regulatory alignment. The MDA6940C is obsolete and subject to discontinuation.

Q: Are there any applications where the LTP-3784E would not be suitable as a substitute?

A: Applications requiring the specific red wavelength (635nm) or maximum brightness (4mcd) should evaluate whether the LTP-3784E's orange-red output (630nm) and lower intensity (2.3mcd) meet design specifications. For general alphanumeric display purposes, compatibility is maintained.