Fault protected 1-Form-A Series - Bidirectional normally open output

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Current Limited SSRs with Thermal Management (ThM) and Voltage Triggered Shutdown (VTS)

Specialized OptoMOS® single-pole, normally open Solid-State Relays (1-Form-A) with an integrated current limit feature that can replace electromechanical relays while enhancing the robustness of wireline interface applications. The active current-limit circuitry in these relays also has a thermal management feature that provides excellent power cross immunity for improved survivability in harsh environments. These features greatly improve the robustness of end systems that use these devices, when compared to systems using relays without integrated current limit. These devices may be used in both AC and DC applications.

CPC1540, CPC1563, and CPC1593 incorporate an additional safety feature, Voltage Triggered Shutdown (VTS), that quickly shuts the device down if a voltage transient, above the VTS threshold, occurs in the load while current limiting is in effect. These devices are ideal for use in noisy environments where such transients can be expected.

Features & Benefits:

  • Low drive current
  • High reliability
  • Provides galvanic input to output isolation


  • Replace electromechanical relays
  • Replace mechanical switches
  • Implement computer control of electromechanical circuits

Access specifications, certifications, check availability and order parts below

Catalog #Blocking Voltage (VP)Load Current max. AC/DC (mA)Load Current max. DC-only (mA)Current Limit max. AC/DC (mA)Current Limit max. DC-only (mA)On-Resistance AC/DC (Ω)On-Resistance DC-only (Ω)VTS Threshold Minimum (V)Input Control Current (mA)Switching Speeds ton / toff (ms)CommentPackage TypePart DatasheetPartner ECAD ModelsStockSamplesCompare
CPC1510250200350450920153.7522 / 2Industrial ApplicationsDIP/SMD-6PartCPC1510CheckOrder
CPC1511Y230450140042.54 / 2Industrial ApplicationsPSIP-4(8)PartCPC1511YCheckOrder
CPC1540350120250285570256.7510022 / 2PSTN Hook Switch AppsDIP/SMD-6PartCPC1540CheckOrder
CPC15606030060090015005. / 0.4Fast Switching SpeedsDIP/SMD-8PartCPC1560CheckOrder
CPC1561B60100030000.2452.52.5 / 0.51A AC/DC Load Current at up to 60SOIC-16PartCPC1561BCheckOrder
CPC15636001202502855703511.7510022 / 2Telecom Secondary ProtectionDIP/SMD-6PartCPC1563CheckOrder
CPC15936001202502855703511.7517.522 / 2HVACDIP/SMD-6PartCPC1593CheckOrder
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