C331S Solid State Relay - Equivalent & Substitute Parts

Part Overview

The C331S is a Solid State SPST-NO (1 Form A) relay manufactured by Coto Technology in an 8-SOP package configuration. This component is classified as Obsolete, requiring identification of functional equivalents for ongoing design support and component procurement. The C331S serves applications requiring low-voltage DC input control of AC or DC loads up to 350V at 100mA capacity.

Substiute Parts

C331S

Coto TechnologyIn Stock: 4658C331S Datasheet

Current PartRFQ

VOR2142B8T

Vishay Semiconductor Opto DivisionIn Stock: 809VOR2142B8T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the C331S is determined by compatibility across the following critical electrical and mechanical parameters:

Electrical Compatibility Parameters:

• Circuit configuration: SPST-NO (1 Form A) x 2
• Input voltage requirement: 1.36V–1.37V DC
• Load voltage range: Minimum 350V (C331S) to 400V (VOR2142B8T)
• Load current capacity: Minimum 100mA (C331S) to 140mA (VOR2142B8T)
• Output type: AC and DC switching capability

Mechanical Compatibility Parameters:

• Mounting type: Surface Mount
• Termination style: Gull Wing
• Package footprint: 8-pin SOP/SMD configurations

The VOR2142B8T from Vishay Semiconductor Opto Division satisfies substitution criteria with equivalent input voltage (1.36VDC), enhanced load voltage rating (400V), increased current capacity (140mA), and compatible surface mount gull wing termination. Both components maintain ROHS3 compliance.

Parameter Comparison

Engineering Selection Recommendations

C331S (Coto Technology): Obsolete status eliminates this component for new designs. Existing inventory supports legacy system maintenance only.

VOR2142B8T (Vishay Semiconductor Opto Division): Active product status with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1) supports long-term supply chain continuity. Enhanced electrical performance (400V load rating, 140mA capacity) provides design margin for existing 350V/100mA applications. On-state resistance increase (24Ω to 27Ω) remains within acceptable performance range for solid state relay applications.

Frequently Asked Questions (FAQ)

Q: Can the VOR2142B8T directly replace the C331S in existing designs?

A: Direct replacement is supported for applications operating within C331S electrical specifications (≤350V load, ≤100mA current, 1.37VDC input). The VOR2142B8T provides enhanced voltage and current ratings. Pin configuration compatibility requires verification against schematic and PCB layout specifications.

Q: What is the primary advantage of VOR2142B8T substitution?

A: Active product status ensures long-term availability. The component provides superior load voltage capability (400V vs. 350V) and higher current capacity (140mA vs. 100mA), offering design margin for legacy system updates.

Q: Are both components package-compatible?

A: Both components use gull wing surface mount termination with 8-pin configurations. The VOR2142B8T package footprint (0.300", 7.62mm) differs from the C331S (0.173", 4.40mm). Physical layout compatibility must be confirmed for retrofitting applications.

Q: What compliance certifications apply to both components?

A: Both components carry ROHS3 compliance and REACH Unaffected status, supporting regulatory requirements in consumer and industrial applications.

Q: Is on-state resistance change (24Ω to 27Ω) significant for substitution?

A: The 3Ω increase represents a 12.5% rise in maximum resistance. For 100mA load current, this generates an additional voltage drop of 0.3V across the relay. Design thermal and voltage margin analysis determines acceptability in specific applications.