MICROSMD190LR-2 Equivalent & Substitute Parts

Part Overview

The MICROSMD190LR-2 is a Polymeric PTC Resettable Fuse manufactured by Littelfuse Inc., rated for 6V maximum voltage with a 1.9A hold current. This component is designed for surface mount applications in the 1210 (3225 Metric) package format with a concave profile. The product is currently classified as Obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity.

Substiute Parts

MICROSMD190LR-2

Littelfuse Inc.In Stock: 16155MICROSMD190LR-2 Datasheet

Current PartRFQ

1210L200SLYR

Littelfuse Inc.In Stock: 146911210L200SLYR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 1210L200SLYR qualifies as a direct substitute for the MICROSMD190LR-2 based on the following critical parameters:

Electrical compatibility is established through matching voltage rating (6V maximum), identical package format (1210 / 3225 Metric with concave profile), and equivalent mechanical dimensions (0.127" L x 0.102" W). Both components are Polymeric PTC Resettable Fuses from Littelfuse Inc., ensuring functional equivalence within the same product family.

The substitute part demonstrates improved specifications in several areas: Current - Hold (Ih) increases from 1.9A to 2A, Current - Trip (It) decreases from 4.9A to 4A, and Time to Trip improves from 4s to 3s. Thickness is reduced from 0.039" (1.00mm) to 0.028" (0.70mm), providing better board space efficiency. Resistance - Initial (Ri) improves from 6 mOhms to 5 mOhms minimum.

The substitute part carries Active product status with expanded operating temperature range (-40°C to 85°C), enhanced certifications (cURus, TUV), and improved moisture sensitivity rating (MSL 1 vs. 2A), indicating superior long-term reliability and availability.

Parameter Comparison

Engineering Selection Recommendations

The 1210L200SLYR is the appropriate substitute for the obsolete MICROSMD190LR-2. The substitute part maintains identical electrical ratings (6V maximum voltage, 50A maximum current) and mechanical compatibility (1210 package, identical footprint dimensions). Both components satisfy ROHS3 compliance requirements.

The substitute part offers the advantage of Active product status, ensuring continued availability and manufacturing support. Enhanced certifications (cURus, TUV) and improved moisture sensitivity rating (MSL 1) provide superior long-term reliability compared to the obsolete original part. The reduced thickness (0.028" vs. 0.039") offers improved board space efficiency without compromising electrical performance.

Frequently Asked Questions (FAQ)

Q: Can the 1210L200SLYR be used as a direct replacement for the MICROSMD190LR-2 in existing designs?

A: Yes. Both components share identical voltage ratings (6V), package format (1210 / 3225 Metric, Concave), and mechanical dimensions (0.127" L x 0.102" W). The footprint and mounting requirements are equivalent, allowing direct PCB substitution.

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

A: The substitute part features a slightly higher hold current (2A vs. 1.9A), faster trip response (3s vs. 4s), and lower initial resistance (5 mOhms vs. 6 mOhms). These represent performance improvements rather than incompatibilities.

Q: Why is the MICROSMD190LR-2 classified as Obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. The 1210L200SLYR represents the current-generation equivalent from the same manufacturer, offering improved specifications and ongoing support.

Q: Are there any thickness considerations for board assembly?

A: The substitute part is thinner (0.028" vs. 0.039"), which provides additional clearance and may improve board layout flexibility. This does not affect electrical performance or compatibility.

Q: Do both parts meet the same compliance standards?

A: Both parts are ROHS3 compliant. The substitute part carries additional certifications (cURus, TUV) compared to the original part (CSA, UL), indicating broader regulatory acceptance.

Q: What is the moisture sensitivity difference between these parts?

A: The original part has MSL 2A (4 weeks), while the substitute has MSL 1 (unlimited). This indicates the substitute part has superior moisture resistance and requires less stringent storage conditions.