LAA127LSTR Solid State Relay - Equivalent & Substitute Parts

Part Overview

The LAA127LSTR is an IXYS OptoMOS® solid state relay (SSR) configured as a SPST-NO (Single Pole Single Throw - Normally Open) relay with dual channels in an 8-SMD surface mount package. This component is designed for switching AC and DC loads up to 250V with a maximum load current of 170mA. The part is currently active in production with full RoHS3 compliance and unlimited moisture sensitivity rating (MSL 1).

Equivalent and substitute parts are identified when component availability is limited, supply chain disruptions occur, or design flexibility is required while maintaining functional compatibility within specified electrical and mechanical parameters.

Substiute Parts

LAA127LSTR

IXYS Integrated Circuits DivisionIn Stock: 3035LAA127LSTR Datasheet

Current PartRFQ

LH1522AACTR

Vishay Semiconductor Opto DivisionIn Stock: 3349LH1522AACTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LAA127LSTR is determined by the following critical parameters:

• Circuit Configuration: Must be SPST-NO (1 Form A) x 2 dual-channel configuration
• Package Type: Must be 8-SMD (0.300", 7.62mm) with Gull Wing termination for PCB compatibility
• Mounting Method: Surface mount only
• Output Capability: Must support both AC and DC load switching
• Voltage Rating: Load voltage range must accommodate 0V ~ 250V operation
• Load Current: Must support minimum 170mA switching capacity
• On-State Resistance: Maximum 15 Ohms on-state resistance
• Input Voltage: 1.2VDC nominal input trigger voltage
• Compliance: RoHS3 compliant, MSL 1 rating

The LH1522AACTR from Vishay Semiconductor Opto Division qualifies as a substitute based on matching package geometry, circuit topology, mounting method, and compliance certifications. Parameter variations exist within acceptable operational ranges for specific applications.

Parameter Comparison

Engineering Selection Recommendations

Both the LAA127LSTR and LH1522AACTR are active production components with full RoHS3 compliance and unlimited moisture sensitivity ratings, making them suitable for industrial and commercial applications requiring environmental compliance.

The LAA127LSTR provides higher load current capacity (170mA versus 120mA) and extended voltage rating (250V versus 200V), making it the preferred choice for applications requiring maximum switching headroom.

The LH1522AACTR offers lower on-state resistance (10 Ohms versus 15 Ohms), resulting in reduced power dissipation during conduction. This substitute is appropriate for applications where load current does not exceed 120mA and load voltage remains below 200V.

Both components share identical package geometry, termination style, and mounting method, ensuring direct PCB footprint compatibility without layout modifications.

Frequently Asked Questions (FAQ)

Q: Can the LH1522AACTR directly replace the LAA127LSTR on existing PCBs?

A: Yes. Both components use identical 8-SMD (0.300", 7.62mm) package geometry with Gull Wing termination, enabling direct footprint compatibility without PCB redesign.

Q: What are the load current limitations when substituting?

A: The LH1522AACTR supports maximum 120mA load current compared to the LAA127LSTR's 170mA rating. Applications requiring load currents above 120mA must use the LAA127LSTR.

Q: Are there voltage rating differences between these parts?

A: Yes. The LAA127LSTR supports load voltages up to 250V, while the LH1522AACTR is rated to 200V maximum. Applications requiring operation above 200V must use the LAA127LSTR.

Q: Do both parts have the same input trigger voltage?

A: Input voltages are nominally equivalent (1.2VDC versus 1.26VDC), with the LH1522AACTR requiring slightly higher input voltage. Both operate within standard logic-level control circuits.

Q: Are both parts RoHS3 compliant?

A: Yes. Both the LAA127LSTR and LH1522AACTR are ROHS3 compliant with MSL 1 (unlimited) moisture sensitivity ratings, suitable for standard manufacturing and storage conditions.

Q: Which part has lower power dissipation?

A: The LH1522AACTR exhibits lower on-state resistance (10 Ohms versus 15 Ohms), resulting in reduced resistive heating during load switching. For applications with continuous or high-frequency switching, this characteristic may provide thermal advantages within the 120mA current limit.