A scannable data synchronizer including an input circuit, first and second pass gates, first and second inverters, and a gate controller. The input circuit drives the data nodes to opposite logic states in response to an asynchronous input data signal in a normal mode and in response to scan data in a scan test mode. Each pass gate is coupled between one of the data nodes and a corresponding one of the capture nodes, and each has at least one control terminal. The inverters are cross-coupled between the second capture nodes. The gate controller can keep the pass gates at least partially open during a metastable condition of the capture nodes, and can close the pass gates when both capture nodes stabilize to opposite logic states. In the scan test mode, the scan data is used to test the latch or register functions of the scannable data synchronizer.

A tristate output buffer includes a first branch with a first buffer, and a second branch with a second buffer. The first buffer includes a supply port, a ground port, an output port, two switchable semiconductor elements of a first type, and two switchable semiconductor elements of a second type. Switching behavior of the switchable semiconductor elements of the first type differs from switching behavior of the switchable semiconductor elements of the second type. The two switchable semiconductor elements of the first type are connected in series and are between the supply port and the output port such that they can be put in a conductive state independent of each other. The two switchable semiconductor elements of the second type are connected in series and are between the ground port and the output port such that they can be put in a conductive state independent of each other.

A buffer circuit includes a first MOSFET including a first source electrode, a first gate electrode, and a first drain electrode, and a second MOSFET, which includes a second source electrode, a second gate electrode, and a second drain electrode, and is same in polarity as the first MOSFET, and the first gate electrode and the second gate electrode are electrically connected to each other.

According to an embodiment, a circuit is described comprising a plurality of flip-flops, a control circuit configured to provide a control signal to each flip-flop of the plurality of flip-flops and an integrity checking circuit connected to the control circuit and to the plurality of flip-flops configured to check whether the flip-flops receive the control signal as provided by the control circuit.

According to an embodiment, a circuit is described comprising a plurality of flip-flops, a control circuit configured to provide a control signal to each flip-flop of the plurality of flip-flops and an integrity checking circuit connected to the control circuit and to the plurality of flip-flops configured to check whether the flip-flops receive the control signal as provided by the control circuit.

A fail-safe device may be coupled to a main device for actuating a switch responsive to a failure. The fail-safe device may include a fail-safe circuit, and an isolation trench surrounding the fail-safe circuit and isolating the fail-safe circuit from the main device. The fail-safe device may include an internal power supply connection, an internal reference voltage connection, a self-biased drive block configured to drive the at least one switch, and a receiver configured to receive failure signals from the main device.

A fail-safe device may be coupled to a main device for actuating a switch responsive to a failure. The fail-safe device may include a fail-safe circuit, and an isolation trench surrounding the fail-safe circuit and isolating the fail-safe circuit from the main device. The fail-safe device may include an internal power supply connection, an internal reference voltage connection, a self-biased drive block configured to drive the at least one switch, and a receiver configured to receive failure signals from the main device.

A system and method to manage a single event latched (SEL) condition, the method including operations to monitor, for a predetermined condition associated with single event latched (SEL) states, a reset signal output from a watchdog device to a microprocessor, wherein the reset signal is responsive to a malfunction condition associated with the microprocessor. The method further includes operations to control provision of power to the microprocessor in response to detection of the predetermined condition.

A fail-safe safety switching device comprises first and second input channels for receiving first and second input signals, and a first testing arrangement for testing the first and second input channels. The first input channel comprises a first entry circuit and a first threshold element connected via a first coupling element to a second testing arrangement and a first transition circuit in a galvanically isolated manner. The second input channel comprises a second entry circuit and a second threshold element connected via a second coupling element to a third testing arrangement and a second transition circuit in a galvanically isolated manner. The first testing arrangement comprises a third coupling element, a ground terminal and a group testing terminal. The first and second threshold elements are connected to the ground terminal and via the third coupling element to the group testing terminal in a galvanically isolated manner.

A fail-safe safety switching device comprises first and second input channels for receiving first and second input signals, and a first testing arrangement for testing the first and second input channels. The first input channel comprises a first entry circuit and a first threshold element connected via a first coupling element to a second testing arrangement and a first transition circuit in a galvanically isolated manner. The second input channel comprises a second entry circuit and a second threshold element connected via a second coupling element to a third testing arrangement and a second transition circuit in a galvanically isolated manner. The first testing arrangement comprises a third coupling element, a ground terminal and a group testing terminal. The first and second threshold elements are connected to the ground terminal and via the third coupling element to the group testing terminal in a galvanically isolated manner.