In various examples, faults are detected based at least in part on result value(s) generated by hardware component(s) by performing one or more diagnostic tests in accordance with a diagnostic test pattern. The diagnostic test pattern may be used to perform an assessment of functionality of the hardware component(s) by causing the hardware component(s) to generate the result value(s), which may be used to identify one or more hardware faults (e.g., by comparing the result value(s) to expected value(s)).

An example process for determining electrical path lengths includes: injecting current into a transmission line having a known capacitance per unit of length; determining a rate of change in voltage on the transmission line in response to the current; determining a capacitance of the transmission line based on the change in voltage; and determining an electrical path length of the transmission line based on the determined capacitance of the transmission line and the known capacitance per unit of length.

Test apparatus measuring relative frequency response of first and second microphones includes a rotatable carrier. First and second microphones are sealingly clamped against a mounting surface of the carrier aligned with first and second apertures therein, such apertures lying equidistant from, and on opposite sides of, the carrier's axis of rotation. The carrier initially positions the first microphone closest to an audible signal source, and the responses of the microphones to an audible excitation signal are measured. The carrier is rotated 180 degrees, and the measurements are repeated. Elongated strips of gasket material are used to align the microphones and to form a seal with the carrier. When microphones are mounted deep within an audio device, the audio device is sealingly clamped against a mounting plate, sequentially aligning the mounting plate aperture with first and second apertures of the audio device housing corresponding to first and second microphones disposed therein.

Test apparatus measuring relative frequency response of first and second microphones includes a rotatable carrier. First and second microphones are sealingly clamped against a mounting surface of the carrier aligned with first and second apertures therein, such apertures lying equidistant from, and on opposite sides of, the carrier's axis of rotation. The carrier initially positions the first microphone closest to an audible signal source, and the responses of the microphones to an audible excitation signal are measured. The carrier is rotated 180 degrees, and the measurements are repeated. Elongated strips of gasket material are used to align the microphones and to form a seal with the carrier. When microphones are mounted deep within an audio device, the audio device is sealingly clamped against a mounting plate, sequentially aligning the mounting plate aperture with first and second apertures of the audio device housing corresponding to first and second microphones disposed therein.

An example process for determining electrical path lengths includes: injecting current into a transmission line having a known capacitance per unit of length; determining a rate of change in voltage on the transmission line in response to the current; determining a capacitance of the transmission line based on the change in voltage; and determining an electrical path length of the transmission line based on the determined capacitance of the transmission line and the known capacitance per unit of length.

According to an embodiment, a digital circuit with N number of redundant flip-flops is provided, each having a data input coupled to a common data signal. The digital circuit operates in a functional mode and a test mode. During test mode, a first flip-flop is arranged as part of a test path and N1 flip-flops are arranged as shadow logic. A test pattern at the common data signal is provided and a test output signal is observed at an output terminal of the first flip-flop to determine faults within a test path of the first flip-flop. At the same cycle, the test output signals of each of the N1 number of redundant flip-flops is observed through the functional path to determine faults.

According to an embodiment, a digital circuit with N number of redundant flip-flops is provided, each having a data input coupled to a common data signal. The digital circuit operates in a functional mode and a test mode. During test mode, a first flip-flop is arranged as part of a test path and N-1 flip-flops are arranged as shadow logic. A test pattern at the common data signal is provided and a test output signal is observed at an output terminal of the first flip-flop to determine faults within a test path of the first flip-flop. At the same cycle, the test output signals of each of the N-1 number of redundant flip-flops is observed through the functional path to determine faults.

A self-diagnosis circuit (BST1) configured to diagnose a fault detection circuit (20) including a first comparator (CMP1) configured to be fed with a voltage based on a fault sensing target voltage (Vo1) and a first reference voltage (Vref1) includes a voltage switch circuit (50) configured to switch the level of a voltage based on a second reference voltage (Vref2) and output the resulting voltage, a first path switch circuit (51) configured to switch between a path through which the voltage output from the voltage switch circuit is fed to the first comparator and a path through which the voltage based on the fault sensing target voltage is fed to the first comparator, and a control circuit (15) configured to control the voltage switch circuit and the path switch circuit.

A self-diagnosis circuit (BST1) configured to diagnose a fault detection circuit including a first comparator (CMP1) configured to be fed with a voltage based on a fault sensing target voltage (Vo1) and a first reference voltage (Vref1) includes a voltage switch circuit configured to switch the level of a voltage based on a second reference voltage (Vref2) and output the resulting voltage, a first path switch circuit configured to switch between a path through which the voltage output from the voltage switch circuit is fed to the first comparator and a path through which the voltage based on the fault sensing target voltage is fed to the first comparator, and a control circuit configured to control the voltage switch circuit and the path switch circuit.

A method of identifying error patterns during automated device testing comprises receiving a data pattern from a plurality of capture modules programmed on a programmable logic device, wherein the plurality of capture modules are programmable and operable to selectively capture data traffic to be monitored, and wherein the data traffic comprises a flow of traffic between a DUT and the programmable logic device. The method further comprises comparing the data pattern with known signatures in an error signature database. Also, the method comprises correlating the data pattern with one or more matching known signatures in the error signature database and assigning a score to each of the one or more matching known signatures in the error signature database based a level of correlation.