text.skipToContent text.skipToNavigation




Littelfuse CPC1561B Solid-State Relay

Combines current limit and thermal overload protection in a single chip

Littelfuse has launched the CPC1561B, the world’s first 60V/1A fault-protected solid-state relay in a normally-open configuration.

The CPC1561B solid-state relay provides the twin protection functions of current limiting and thermal shut-down, protecting electronics systems from:

  • Short circuits on the relay load output
  • An excessive temperature rise in the system

The CPC1561B relay also implements an automatic reset once the fault condition is eliminated.

The integration of these dual protection functions in a single device reduces component count, saves space and simplifies the board layout. If the relay’s fault protection functions were provided instead with external discrete components, the bill-of-materials cost would rise by at least an extra $0.80.

The CPC1561B is supplied in a 16-pin SOIC package with a footprint of 10.2mm x 7.5mm.

CPC1561B Features

  • Fault-mode protection trigger: 128°C die temperature
  • 3,750Vrms input-to-output isolation
  • 1A maximum load current
  • 60V blocking voltage
  • 0.245Ω on-resistance
  • 2.5mA input control current
  • 1µA off-state leakage current


  • Smart home systems
  • Building automation
  • Security systems
  • Electronic door locks
  • Gaming
  • Instrumentation
  • Battery-powered systems