A method of testing a multiple power domain device includes sending a control signal from a test controller powered by a switchable power domain to a non-scan test data register powered by an always on power domain. The method further includes setting, using the control signal, a test data register value of the register to enable scan mode by bypassing an isolation cell between an output of the switchable domain and an input of the always on domain and, while the register value continuously enables scan mode: shifting a test pattern into a scan chain including a flip-flop coupled to the isolation cell, capturing a test result from the scan chain, and shifting the test pattern out of the scan chain to observe the test result. The isolation cell is configured to allow or disallow propagation of a signal from the output to the input.

A backplane testing system is provided. Based on the connection relationship and signal transfer relationship of a differential signal transceiver, a backplane and a loop device, the differential signal transceiver generates a set of pseudo random binary sequence (PRBS) as a differential signal, and sends the differential signal and receives the returned differential signal, and then determines whether the differential signals sent and received are the same; and the differential signal transceiver generates a test signal that conforms to the IEEE-1149.6 boundary scan test standard, and sends the test signal and receives the returned test signal through a second positive differential signal circuit and a second negative differential signal circuit, and then determines whether the test signals sent and received through the second positive differential signal circuit are the same and whether the test signals sent and received through the second negative differential signal circuit are the same.

Techniques for a power saving scannable latch output driver in an integrated circuit (IC) are described herein. An aspect includes receiving, by a circuit comprising a scannable latch, a scan signal. Another aspect includes, based on the scan signal being enabled, turning on a scan output driver of the scannable latch, wherein a scan input of the scannable latch propagates through the scannable latch to a scan output based on the scan output driver being turned on. Another aspect includes, based on the scan signal being disabled, turning off the scan output driver, wherein the scan output driver comprises a first p-type field effect transistor (PFET) and a first n-type field effect transistor (NFET), wherein a gate of the first PFET and a gate of the first NFET are connected to an output of a latch of the scannable latch.

A test system is provided. The test system includes a printed circuit board (PCB) and a plurality of integrated circuits (ICs) mounted on the PCB. A first IC of the plurality includes a first test circuit having a first test access port (TAP) controller. A second IC of the plurality includes a second test circuit having a second TAP controller and an embedded tester having a test data output coupled to a test data input of the first TAP controller by way of a link circuit. The embedded tester is configured to provide test control signals to the first TAP controller and the second TAP controller.

A method and apparatus for evaluating and optimizing a signaling system is described. A pattern of test information is generated in a transmit circuit of the system and is transmitted to a receive circuit. A similar pattern of information is generated in the receive circuit and used as a reference. The receive circuit compares the patterns. Any differences between the patterns are observable. In one embodiment, a linear feedback shift register (LFSR) is implemented to produce patterns. An embodiment of the present disclosure may be practiced with various types of signaling systems, including those with single-ended signals and those with differential signals. An embodiment of the present disclosure may be applied to systems communicating a single bit of information on a single conductor at a given time and to systems communicating multiple bits of information on a single conductor simultaneously.

A test system is provided. The test system includes a printed circuit board (PCB) and a plurality of integrated circuits (ICs) mounted on the PCB. A first IC of the plurality includes a first test circuit having a first test access port (TAP) controller. A second IC of the plurality includes a second test circuit having a second TAP controller and an embedded tester having a test data output coupled to a test data input of the first TAP controller by way of a link circuit. The embedded tester is configured to provide test control signals to the first TAP controller and the second TAP controller.

Implementations described herein relate to a core and interface scan testing. In some implementations, an integrated circuit may include input scan flip-flops (ISFFs) arranged in multiple ISFF stages that include a first ISFF stage and a second ISFF stage. Inputs to the first ISFF stage are connected to inputs of the integrated circuit. Inputs to the second ISFF stage are connected to outputs of a logic component that is connected to outputs of the first ISFF stage. The integrated circuit may include output scan flip-flops (OSFFS) arranged in multiple OSFF stages that include a first OSFF stage and a second OSFF stage. Outputs from the first OSFF stage are connected to outputs of the integrated circuit. Outputs from the second OSFF stage are connected to inputs of a logic component that is connected to inputs of the first OSFF stage. The integrated circuit may include core scan flip flops.

A pin connection testing system for connector, and a method thereof are disclosed. In the pin connection testing system, a JTAG instruction is used to control a PLD, to drive the demultiplexer to transmit each to-be-tested signal, which is from the connector, to a first line or a second line; and, when the to-be-tested signal is transmitted to the first line, the to-be-tested signal is converted from analog to digital and encoded, and then transmitted to I/O pins of the PLD for reading; and, when the JTAG command is transmitted to the second line, the PLD reads the statuses of the I/O pins electrically connected to the second line; and then the PLD generates a test result according to the to-be-tested signals and the read I/O pins. Therefore, the technical effect of improving convenience in testing the connection status of the connector can be achieved.

A reconfigurable scan network in a circuit is configured such that a first scan path is used if a programmable component has no stuck-at fault and a second scan path is used if the programmable component has a stuck-at fault. A test pattern having a length equal to a length of the second path is shifted into the reconfigurable scan network, and a part or a whole of the test pattern is then shifted out from the reconfigurable scan network. The part or the whole of the test pattern being shifted out is analyzed to determine whether the programmable component has the stuck-at fault.

In one example a controller comprises logic, at least partially including hardware logic, configured to implement a first iteration of an interference test on a communication interconnect comprising a victim lane and a first aggressor lane by generating a first set of pseudo-random patterns on the victim lane and the aggressor lane using a first seed and implement a second iteration of an interference test by advancing the seed on the first aggressor lane. Other examples may be described.