Fault detection circuitry and a corresponding method are disclosed. A count value that is indicative of the switching period of a PWM signal is determined and it is determined whether this count value is between a first threshold and a second threshold. An error signal is generated when the switching period is not between the first and the second threshold. A count value that is indicative of the switch-on duration of the PWM signal is determined and compared with a switch-on threshold in order to determine whether the switch-on duration is greater than a maximum switch-on duration. A count value that is indicative of the switch-off duration of the PWM signal is determined and compared with a switch-off threshold in order to determine whether the switch-off duration is greater than a maximum switch-off duration. Error signals can be generated when the durations are greater than the maximum durations.

A circuit structure and a method for supressing single event transients (SETs) or glitches in digital electronic circuits are provided. The circuit includes a first input which receives an output of a digital electronic circuit and a second input which receives a redundant or duplicated output of the digital electronic circuit. The circuit includes only four two-input gates of two different kinds selected from AND, OR, NAND and NOR gates. The four two-input gates being arranged so that a final circuit output is impervious to a change in a logic level of only the first input or only the second input, and the final circuit output is equivalent to the logic level of the first and second inputs when the logic level of the first and second inputs match.

A circuit provides fail safe protection of an input/output (I/O) circuit of a chip. The I/O circuit comprises an I/O pad connected to one or more other chips via an I/O bus. The circuit comprise a supply and failsafe detector component. The supply and failsafe detector component generates an I/O supply output signal. The I/O supply output signal has a low voltage value when the I/O supply voltage of the chip is below a medium voltage level and the I/O supply output signal having a high voltage value when the I/O supply voltage of the chip is above the medium voltage level. The medium voltage is above a threshold voltage of the transistor of the I/O circuit and below the high voltage value. The circuit uses the I/O supply output signal to provide a reference voltage as input to the transistor of the I/O circuit.

A circuit provides fail safe protection of an input/output (I/O) circuit of a chip. The I/O circuit comprises an I/O pad connected to one or more other chips via an I/O bus. The circuit comprise a supply and failsafe detector component. The supply and failsafe detector component generates an I/O supply output signal. The I/O supply output signal has a low voltage value when the I/O supply voltage of the chip is below a medium voltage level and the I/O supply output signal having a high voltage value when the I/O supply voltage of the chip is above the medium voltage level. The medium voltage is above a threshold voltage of the transistor of the I/O circuit and below the high voltage value. The circuit uses the I/O supply output signal to provide a reference voltage as input to the transistor of the I/O circuit.

Various implementations described herein are directed to a device having a scan chain that receives a multi-bit input, provides a multi-bit output, and provides a multi-bit multiplexer output based on the multi-bit input and the multi-bit output. The device may have an error-bit generator that receives the multi-bit multiplexer output, receives a portion of the multi-bit input, receives a portion of the multi-bit output, and provides an error-bit output based on the multi-bit multiplexer output, the portion of the multi-bit input, and the portion of the multi-bit output.

A digital integrated circuit comprising a logic array comprises a functional logic block, a logic unit for detecting transient errors affecting the functional logic block, an input FIFO memory for supplying the functional logic block with samples, an output FIFO memory for receiving samples output from the functional logic block, a buffer memory that is supplied with samples by the input FIFO memory, and a logic control unit that is able to control read access to the input FIFO memory and write access to the output FIFO memory and that is configured, when an error is detected by the transient-error-detecting logic unit, to reset the transient-error-detecting logic unit and the functional logic block, to suspend write access to the output FIFO memory and to switch the input of the functional logic block to the output of the buffer memory.

A signal transmission device that transmits a driving signal for a power transistor from a primary circuit system to a secondary circuit system while isolating between the primary and secondary circuit systems includes: a first fault detection circuit configured to detect a fault in the primary circuit system; a second fault detection circuit configured to detect a fault in the secondary circuit system; a first signal transmission path configured to transmit the result of detection by the second fault detection circuit from the secondary circuit system to the primary circuit system while isolating between the primary and secondary circuit systems; and a self-test circuit configured to perform a self-test on each of the first fault detection circuit, the second fault detection circuit, and the first signal transmission path.

A trim/test interface in a packaged integrated circuit device prevents high through-current between pins of the IC device and trim/test interface digital logic within the IC device using a floating-pin-tolerant always-on CMOS input buffer. The always-on buffer uses a coupling capacitor at its input to block signals at DC and a weak-latch feedback path to ensure that intermediate or floating inputs are provided through the buffer only at one of two digital levels (e.g., those provided by a ground pin GND and by a high supply voltage pin VDD). The described interfaces and methods provide for false-entry-free test mode activation for IC devices with a low pin count, where there are a limited number of pins to cover all test/trim functions, or in which only analog, no-connect, or failsafe pins are available for trim or test mode entry control or trim or test data input.

A trim/test interface in a packaged integrated circuit device prevents high through-current between pins of the IC device and trim/test interface digital logic within the IC device using a floating-pin-tolerant always-on CMOS input buffer. The always-on buffer uses a coupling capacitor at its input to block signals at DC and a weak-latch feedback path to ensure that intermediate or floating inputs are provided through the buffer only at one of two digital levels (e.g., those provided by a ground pin GND and by a high supply voltage pin VDD). The described interfaces and methods provide for false-entry-free test mode activation for IC devices with a low pin count, where there are a limited number of pins to cover all test/trim functions, or in which only analog, no-connect, or failsafe pins are available for trim or test mode entry control or trim or test data input.

Described herein is a method implemented by circuitry for providing fault tolerance in a combinational circuit. The circuitry identifies sensitive gates of the circuit that require protection from at least one of a first type of fault and a second type of fault. Further, circuitry computes for each first type of transistor included in the sensitive gate, a first failure probability, and for each second type of transistor included in the sensitive gate, a second failure probability. The circuitry calculates a first parameter corresponding to a number of the first type of transistors for which the computed first failure probabilities exceed a first predetermined threshold and a second parameter corresponding to a number of second type of transistors for which the computed second failure probabilities exceed a second predetermined threshold to determine a protection type based on an area overhead constraint.