MDSR-7-15-20 Equivalent & Substitute Parts

Part Overview

The MDSR-7-15-20 is a glass body reed switch manufactured by Littelfuse Inc., configured as a SPST-NO (Single Pole Single Throw - Normally Open) device. This component is designed for applications requiring reliable switching of low-level signals with a rated power of 10W and switching current capacity of 350mA (AC) or 500mA (DC) at 140V AC / 200V DC. The part is currently in active production status with 944 units in stock. Alternative equivalent parts may be required due to inventory constraints, packaging preferences, or specific application requirements where substitute parts meet identical electrical and mechanical specifications.

Substiute Parts

MDSR-7-15-20

Littelfuse Inc.In Stock: 962MDSR-7-15-20 Datasheet

Current PartRFQ

FLEX-14-15-20

LittelfuseIn Stock: 3978FLEX-14-15-20 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The FLEX-14-15-20 qualifies as a direct equivalent substitute for the MDSR-7-15-20 based on the following critical parameters that determine functional interchangeability:

Electrical Equivalence Criteria:

• Identical circuit configuration (SPST-NO)
• Identical operate range (15 ~ 20AT)
• Identical switching current ratings: 350mA (AC), 500mA (DC)
• Identical switching voltage ratings: 140V (AC), 200V (DC)
• Identical rated power: 10W
• Identical operating temperature range: -40°C ~ 125°C

Mechanical Compatibility Criteria:

• Identical mounting type (Through Hole)
• Identical termination style (Axial)
• Compatible body dimensions within acceptable tolerance for through-hole PCB assembly

Compliance Equivalence:

• Both parts are ROHS3 Compliant
• Both parts have REACH Unaffected status
• Both parts carry EAR99 ECCN classification

The substitute part maintains full functional equivalence across all critical electrical parameters while offering improved current-carry capacity (1A DC vs. 800mA DC) and slightly faster operate time (0.55ms vs. 0.6ms).

Parameter Comparison

Engineering Selection Recommendations

Both the MDSR-7-15-20 and FLEX-14-15-20 are active production components from Littelfuse Inc. with identical electrical specifications and full compliance certifications (ROHS3, REACH Unaffected, EAR99). Selection between these parts should be based on:

Inventory and Packaging Availability: The MDSR-7-15-20 is available in bulk packaging with 944 units in stock. The FLEX-14-15-20 is available in box packaging with 3942 units in stock. Choose based on procurement requirements and packaging format preference.

Physical Dimensions: The FLEX-14-15-20 has slightly larger overall dimensions (1.744" vs. 1.590" length, 0.090" vs. 0.071" body diameter). Verify PCB layout and mechanical clearances before substitution if space constraints are critical.

Performance Characteristics: The FLEX-14-15-20 offers marginally improved performance with faster operate time (0.55ms vs. 0.6ms) and higher DC current-carry capacity (1A vs. 800mA). These enhancements do not affect functional equivalence but may provide operational benefits in demanding applications.

Both parts meet all compliance requirements for direct substitution in applications designed for SPST-NO reed switches with 10W rated power and 140V AC / 200V DC switching capability.

Frequently Asked Questions (FAQ)

Q: Can the FLEX-14-15-20 be used as a direct replacement for the MDSR-7-15-20 in existing designs?

A: Yes. The FLEX-14-15-20 meets all critical electrical specifications: identical SPST-NO circuit configuration, operate range (15 ~ 20AT), switching current (350mA AC / 500mA DC), switching voltage (140V AC / 200V DC), and rated power (10W). Both parts are through-hole axial termination devices with identical operating temperature range (-40°C ~ 125°C). Verify PCB layout accommodates the slightly larger body dimensions (0.090" Dia vs. 0.071" Dia).

Q: What are the key differences between these two parts?

A: The primary differences are physical dimensions and packaging format. The FLEX-14-15-20 is 0.154" longer (1.744" vs. 1.590") and has a larger body diameter (0.090" vs. 0.071"). The FLEX-14-15-20 also provides higher DC current-carry capacity (1A vs. 800mA) and faster operate time (0.55ms vs. 0.6ms). Electrical switching specifications are identical.

Q: Are there any compliance or certification differences?

A: No. Both parts carry identical compliance certifications: ROHS3 Compliant, REACH Unaffected status, and EAR99 ECCN classification. Both are active production components from Littelfuse Inc.

Q: Which part should be selected for new designs?

A: Either part is suitable for new designs. The FLEX-14-15-20 offers improved performance characteristics (faster switching, higher current-carry capacity) and greater inventory availability (3942 units vs. 944 units). Select based on PCB space constraints and packaging format requirements.

Q: Are there any thermal or environmental limitations to consider?

A: Both parts operate across the identical temperature range (-40°C ~ 125°C) and carry MSL 1 (Unlimited) moisture sensitivity rating. No additional environmental considerations differentiate these parts.