LCA125STR Solid State Relay - Equivalent & Substitute Parts

Part Overview

The LCA125STR is an active SPST-NO (1 Form A) solid state relay manufactured by IXYS Integrated Circuits Division, part of the OptoMOS® series. This surface mount component operates with a 1.2VDC input signal and handles loads up to 350V at 170mA, making it suitable for AC and DC switching applications. The component is RoHS3 compliant, REACH unaffected, and carries unlimited moisture sensitivity rating (MSL 1). Finding equivalent substitute parts becomes necessary when managing supply chain continuity, inventory optimization, or when the primary part reaches end-of-life status.

Substiute Parts

LCA125STR

IXYS Integrated Circuits DivisionIn Stock: 2193LCA125STR Datasheet

Current PartRFQ

LH1500AABTR

Vishay Semiconductor Opto DivisionIn Stock: 2156LH1500AABTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LCA125STR is determined by strict alignment of the following critical parameters:

Mandatory Matching Parameters:

• Circuit configuration: SPST-NO (1 Form A)
• Package type: 6-SMD (0.300", 7.62mm)
• Termination style: Gull Wing
• Mounting type: Surface Mount
• Load voltage range: 0V to 350V
• Output type: AC and DC capability
• Product status: Active

Allowable Parameter Variations:

• Input voltage: Within compatible logic levels (1.2VDC to 1.25VDC)
• Load current: Equal to or greater than 170mA
• On-state resistance: Equal to or less than 16 Ohms
• Compliance certifications: RoHS3 and REACH status maintained

The LH1500AABTR from Vishay Semiconductor Opto Division qualifies as a direct substitute based on these criteria.

Parameter Comparison

Engineering Selection Recommendations

The LH1500AABTR is an active, RoHS3-compliant substitute for the LCA125STR. Both components maintain identical compliance status under REACH regulations and carry the same unlimited moisture sensitivity rating. The substitute part operates within compatible input voltage specifications and maintains the same load voltage range and package footprint.

Selection between these parts should account for the documented parameter differences: the LH1500AABTR carries a lower maximum load current rating (150mA versus 170mA) and higher on-state resistance (20 Ohms versus 16 Ohms). These differences may impact thermal dissipation and current-handling capacity in applications operating at or near the 170mA specification limit.

Frequently Asked Questions (FAQ)

Q: Can the LH1500AABTR directly replace the LCA125STR in existing designs?

A: The LH1500AABTR shares identical package, termination, mounting type, and load voltage specifications. However, the lower current rating (150mA) and higher on-state resistance (20 Ohms) require evaluation against your specific application current requirements and thermal constraints.

Q: Are there differences in input voltage compatibility?

A: The LCA125STR requires 1.2VDC input, while the LH1500AABTR operates at 1.25VDC. This 0.05VDC difference falls within standard logic-level tolerances and presents no practical compatibility issue for typical control circuits.

Q: Do both parts meet the same regulatory requirements?

A: Yes. Both the LCA125STR and LH1500AABTR are RoHS3 compliant, REACH unaffected, and carry MSL 1 (unlimited) ratings.

Q: What is the impact of the higher on-state resistance in the LH1500AABTR?

A: The 20 Ohm maximum resistance (versus 16 Ohms) results in increased power dissipation at rated current. At 150mA, the LH1500AABTR dissipates up to 0.45W compared to 0.39W for the LCA125STR. Thermal design review is recommended for applications with limited heat dissipation capability.

Q: Are both parts available in the same packaging format?

A: Yes. Both components use 6-SMD (0.300", 7.62mm) packages with gull wing termination, suitable for standard surface mount assembly processes.