STMicroelectronics : VNI8200XP High-side solid-state relay provides full set of protection functions


VNI8200XP: integrated power regulator

STMicroelectronics’ VNI8200XP is a monolithic eight-channel solid-state relay featuring a very low supply current. It has an integrated serial peripheral interface and a high-efficiency 100mA step-down switching regulator operating in peak current-control mode.

The VNI8200XP IC, realised in ST’s VIPower™ technology, is intended to drive any kind of load – resistive, capacitive or inductive – with one side connected to ground.

The device is very well protected against faults. Active-channel current limitation combined with a thermal shut-down capability, independent for each channel, protect the device against overload.

Additional protection functions on the relay include:
• Protection against loss of ground. The VNI8200XP automatically turns off its outputs in case of ground disconnection.
• Under-voltage shut-down with hysteresis
• Power Good diagnostic indicator
• Output Enable function
• Programmable watchdog
• Case over-temperature protection

The SPI offers selectable 8- or 16-bit operation. Via a Select pin, the user can also choose to operate the device with a parallel interface. Both 8- and 16-bit SPI operations support daisy-chain connections.

The VNI8200XP’s thermal shut-down feature protects the chip from over-temperature and short-circuit events. In overload conditions, the channel turns off and on again automatically after the IC’s temperature decreases below a threshold fixed by a temperature hysteresis. Channels which are not overloaded continue to operate normally.

An integrated step-down voltage regulator provides a supply voltage to the internal indicator-LED matrix driver and logic output buffers, and may be used to supply external optocouplers if the application requires isolation.


  • 1A output current per channel
  • 5.3mA supply current with all channels on
  • 5V- and 3.3V-compatible I/Os
  • Fast demagnetisation of inductive loads
  • Withstands ESD strikes up to 2kV


  • Programmable Logic Controllers (PLCs)
  • Industrial PC peripheral inputs/outputs
  • Numerical control machines


The X-NUCLEO-PLC01A1 is an industrial I/O evaluation board, extending an STM32 Nucleo microcontroller main board with PLC functionality. Compatible with the Arduino UNO R3 connector layout, it is based on the VNI8200XP solid-state relay and the CLT01-38SQ7 octal digital termination array.

Orderable Part Number: X-NUCLEO-PLC01A1