Industrial control system with integrated circuit elements partitioned for functional safety and employing watchdog timing circuits

An industrial control system comprising:

• first and second integrated circuit elements communicating first and second field signals, respectively, and first and second activity signals, respectively, the first and second integrated circuit elements each including a watchdog tuning circuit;
• and
• first and second power shut-off components configured to selectively switch between 1) providing power for the first and second field signals, respectively, and 2) removing power from the first and second field signals, respectively,
• wherein the watchdog timing circuit of the first integrated circuit element receives the second activity signal from the second integrated circuit element, and the watchdog timing circuit of the second integrated circuit element receives the first activity signal from the first integrated circuit element,
• wherein the watchdog timing circuit of the first integrated circuit element is configured to cause the second power shut-off component to selectively switch, and the watchdog timing circuit of the second integrated circuit element is configured to cause the first power shut-off component to selectively switch,
• wherein the watchdog timing circuits are each configured to cause the respective power shut-off component to selectively switch to removing power upon detecting an edge of the received activity signal within a first predetermined amount of time, and wherein the watchdog timing circuits are each configured to cause the respective power shut-off component to selectively switch to removing power upon failing to detect an edge of the received activity signal within a second predetermined amount of time.

An industrial control system comprising:

• first and second processors;
• first and second isolators in communication with the first and second processors, the first and second isolators providing electrical isolation for the first and second processors;
• first and second integrated circuit elements in communication with the first and second isolators, the first and second integrated circuit elements providing first and second field signals, respectively, and first and second activity signals, respectively, the first and second integrated circuit elements each including a watchdog timing circuit;
• first and second screw terminals in communication with the first and second field signals, respectively, and
• first and second power shut-off components configured to selectively switch between 1) providing power for the first and second field signals, respectively, and 2) removing power from the first and second field signals, respectively,
• wherein the watchdog timing circuit of the first integrated circuit element receives the second activity signal from the second integrated circuit element, and the watchdog timing circuit of the second integrated circuit element receives the first activity signal from the first integrated circuit element, and
• wherein the watchdog timing circuit of the first integrated circuit element is configured to cause the second power shut-off component to selectively switch, and the watchdog timing circuit of the second integrated circuit element is configured to cause the first power shut-off component to selectively switch.