LH1550AT1 Equivalent & Substitute Parts

Part Overview

The LH1550AT1 is a solid-state relay (SSR) manufactured by Vishay Semiconductor Opto Division, configured as a SPST-NO (Single Pole Single Throw - Normally Open) switching device. This component operates with a 1.25VDC input signal and controls AC/DC loads up to 350V at 120mA maximum current. The device is packaged in a 6-DIP through-hole format with PC pin termination.

The LH1550AT1 carries a Last Time Buy product status, indicating that new production has ceased. This status necessitates identification of equivalent substitute parts to ensure design continuity and procurement availability for ongoing applications and new designs.

Substiute Parts

LH1550AT1

Vishay Semiconductor Opto DivisionIn Stock: 20254LH1550AT1 Datasheet

Current PartRFQ

LH1546AT

Vishay Semiconductor Opto DivisionIn Stock: 20464LH1546AT Datasheet

MFR RecommendedRFQ

AQV210EH

Panasonic Electric WorksIn Stock: 19226AQV210EH Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LH1550AT1 is determined by strict alignment of the following critical parameters:

• Circuit configuration: SPST-NO (1 Form A)
• Package format: 6-DIP (0.300", 7.62mm) with PC pin termination
• Load voltage range: 0V to 350V
• Output capability: AC and DC switching
• On-state resistance: Maximum 28 Ohms (or lower)
• Load current capacity: Minimum 120mA

The identified substitute parts meet these criteria within the allowed electrical and mechanical tolerances for this product category. Substitute parts may exhibit minor variations in input voltage specification and on-state resistance while maintaining functional equivalence for the specified load conditions.

Parameter Comparison

Engineering Selection Recommendations

LH1546AT is the primary substitute for the LH1550AT1. Both components are manufactured by Vishay Semiconductor Opto Division and share identical electrical specifications for load voltage, load current, and on-state resistance. The LH1546AT carries Active product status, ensuring ongoing availability and supply chain continuity. Input voltage specification differs by 0.01VDC (1.26VDC versus 1.25VDC), which is within standard engineering tolerance for solid-state relay applications.

AQV210EH is a secondary substitute manufactured by Panasonic Electric Works under the PhotoMOS™ AQV series. This component meets all critical substitution parameters with identical load voltage range and AC/DC output capability. The AQV210EH provides higher load current capacity (130mA versus 120mA) and lower input voltage requirement (1.14VDC). On-state resistance is specified at 35 Ohms maximum, which exceeds the LH1550AT1 specification by 7 Ohms. The AQV210EH maintains Active product status and full ROHS3 compliance.

Both substitute parts are available in production quantities and carry ROHS3 and REACH compliance certifications matching the original component.

Frequently Asked Questions (FAQ)

Q: Can the LH1546AT directly replace the LH1550AT1 in existing designs?

A: Yes. The LH1546AT is functionally equivalent for all specified load conditions. Both components share identical circuit configuration, package format, load voltage range, load current rating, and on-state resistance specification. The 0.01VDC input voltage difference is within standard operating tolerance.

Q: What is the primary difference between the LH1546AT and AQV210EH?

A: Both are functionally equivalent substitutes. The LH1546AT is manufactured by Vishay and maintains identical on-state resistance (28 Ohms). The AQV210EH is manufactured by Panasonic and offers higher load current capacity (130mA) with lower input voltage requirement (1.14VDC), but specifies higher on-state resistance (35 Ohms maximum). Selection depends on circuit design requirements and supplier availability.

Q: Are all substitute parts available in the same 6-DIP package?

A: Yes. All listed substitute parts are packaged in 6-DIP (0.300", 7.62mm) format with PC pin termination, ensuring mechanical and electrical compatibility with existing PCB layouts.

Q: Do the substitute parts meet the same compliance standards as the LH1550AT1?

A: Yes. Both LH1546AT and AQV210EH are ROHS3 compliant and REACH unaffected, matching the original component's regulatory status.

Q: Why is the LH1550AT1 marked as Last Time Buy?

A: Last Time Buy status indicates that Vishay Semiconductor Opto Division has discontinued new production of this component. The LH1546AT and AQV210EH are active production alternatives that provide equivalent functionality for new designs and ongoing applications.