A clock monitor circuit includes a monitor and a tunable counter. The monitor can monitor a clock under test. The tunable counter can count an integer according to a reference clock and set a target number. If a stable signal relative to the clock under test is toggled, the tunable counter can switch the target number from a large number to a small number. The tunable counter can perform an automatic detection process, so as to transmit a check signal to the monitor. In response to the check signal, if the clock under test is undetectable, the monitor will not transmit any confirmation signal back to the tunable counter, and the tunable counter will gradually increase the integer. When the integer is equal to the target number, the tunable counter generates a failure signal.

Introduced herein is a technique that reliably measures on-die noise of logic in a chip. The introduced technique places a noise measurement system in partitions of the chip that are expected to cause the most noise. The introduced technique utilizes a continuous free-running clock that feeds functional frequency to the noise measurement circuit throughout the noise measurement scan test. This allows the noise measurement circuit to measure the voltage noise of the logic during a shift phase, which was not possible in the conventional noise measurement method. Also, by being able to measure the voltage noise during a shift phase and hence in both phases of the scan test, the introduced technique can perform a more comprehensive noise measurement not only during ATE testing but as part of IST in the field.

A system on chip includes a one-time programmable (OTP) memory configured to store secure data, an OTP controller including at least one shadow register configured to read the secure data from the OTP memory and to store the secure data, a power management unit configured to receive an operation mode signal from an external device and to output test mode information indicating whether an operation mode is a test mode according to the operation mode signal and a test valid signal corresponding to the secure data, and a test circuit configured to receive the test mode information from the power management unit, to receive test data from the external device, and to output a scan mode signal and a test mode signal according to the test data and a test deactivation signal, wherein the test deactivation signal corresponds to development state data indicating a chip development state in the secure data.

Disclosed is a test circuit for testing an integrated circuit core or an external circuit of the integrated circuit core. The test circuit may not only transmit a cell function input to a cell function output using only one multiplexer in a bypass mode, may but also use a clock gating scheme capable of blocking a clock signal from transmitting to a scan flip-flop to hold a capture procedure.

Methods and structures are described for detecting clock anomalies. Example methods include measuring a duration of a first phase of the clock signal, monitoring a duration of a second phase of the clock signal, and determining whether the duration of the second phase has exceeded the measured duration of the first phase. If so, a clock stop detection signal is asserted. Example structures include a detector circuit having an input for sensing the clock signal. The circuit is operable to measure a duration of a first clock phase instance, to monitor a duration of a second clock phase instance, and to assert an output if the duration of the second clock phase instance exceeds the measured duration of the first clock phase instance.

In some examples, an integrated circuit comprises: a TDI input, a TDO output, a TCK input and a TMS input; a TAP state machine (TSM) having an input coupled to the TCK input, an input coupled to the TMS input, an instruction register control output, a TSM data register control (DRC) output, and a TSM state output; an instruction register having an input coupled to the TDI input, an output coupled to the TDO output, and a control input coupled to the instruction register control output of the TAP state machine; router circuitry including a TSM DRC input coupled to the TSM DRC output, a control DRC input coupled to the TSM state output, and a router DRC output; and a data register having an input coupled to the TDI input, an output coupled to the TDO output, and a data register DRC input coupled to the router DRC output.

A reference clock signal of at least one module clock signal associated with each module is delivered. A measurement period is generated and a module whose consumption is to be determined is selected. The frequency of the at least one module clock signal associated with the selected module reduced during the measurement period. A measurement of a first consumption of the device is made in the measurement period. A measurement of a second consumption of the device is made outside the measurement period. The consumption of the selected module is determined from the first and measured first and second consumptions.

The present disclosure provides systems and methods for performing built-in-self-test (BIST) operations without a dedicated clock source. The BIST operations are performed by receiver lanes of a multilane receiver system, wherein at least one receiver lane is configured as synthesized clock source for other receiver lanes configured to perform BIST operations. The at least one receiver lane configured as the synthesized clock source may generate a clock signal and provide the clock signal to the other receiver lanes performing the BIST operations. In some examples, digital control signals may be used for coordinating the enablement of the at least one receiver lane to function as the synthesized clock source and for coordinating the enablement of the other receiver lanes to perform BIST operations.

The disclosure provides a novel method and apparatus for inputting addresses to devices to select the device TAP for access. Further, the disclosure provides a novel method and apparatus for inputting addresses for selecting device TAPs and for inputting commands for commanding circuitry within the device. The inputting of addresses or the inputting of addresses and commands is initiated by a control bit input on TDI that is recognized during the Run Test/Idle, Pause-DR or Pause-IR TAP states.

In some examples, a circuit includes a custom control data register (CCDR) circuit having a scan path. The CCDR circuit includes a shift register and an update register. The shift register is configured to receive scan data from a scan data input (CDR_SCAN_IN) on a first clock edge responsive to a scan enable signal (CDR_SCAN_EN) being enabled. The update register is configured to receive data from the shift register on a second clock edge after the first clock edge when the scan enable (CDR_SCAN_EN) is enabled. The update register data is asserted as a scan data output (CDR_SCAN_OUT). The second scan path includes the scan data input, the shift register, the update register, and the scan data output.