Patent classifications
G01R31/317
CURRENT LOAD CIRCUIT AND CHIP FOR TESTING POWER SUPPLY CIRCUIT
A current load circuit for testing a power supply circuit includes a control circuit and a load generation circuit. The control circuit is configured to generate a reset signal according to a clock signal. The load generation circuit is coupled to the control circuit and has several load configurations. The load generation circuit is configured to provide one of the load configurations as a current load of the load generation circuit according to the clock signal and the reset signal and receive a portion of the supply current provided by the power supply circuit according to the current load to generate an indication signal for indicating a performance of the power supply circuit.
Skew detection system and method to remove unwanted noise due to skewed signals
Various embodiments relate to a skew detector circuit, including: a logic circuit having two inputs configured to generate a logic 1 output when the two inputs have a logic 0 value and generator a logic 0 output when the two input have a logic 1 value; a first level shifter configured to increase the output of the logic circuit to a higher voltage; a second level shifter configured to increase the output of the first level shifter to a higher voltage; and a voltage regulator configured to produce a first voltage for the logic circuit, a second voltage for the first level shifter, and a third voltage for the second level shift.
Unified approach for improved testing of low power designs with clock gating cells
An apparatus includes a core logic circuit, one or more integrated clock-gating (ICG) cells, and one or more ICG control cells (ICCs). The core logic circuit generally comprises a plurality of flip-flops. The plurality of flip-flops may be connected to form one or more scan chains. Each of the one or more integrated clock-gating (ICG) cells may be configured to gate a clock signal of a respective one of the one or more scan chains. Each of the one or more ICG control cells may be configured to control a respective one or more of the one or more ICG cells.
Scan channel slicing for compression-mode testing of scan chains
Scan channel slicing methods and systems for testing of scan chains in an integrated circuit (IC) reduce the number of test cycles needed to effectively test all the scan chains in the IC, reducing the time and cost of testing. In scan channel slicing, rather than loading and unloading into scan chains high-power patterns having numerous switching transitions over the length of each scan chain, loading and unloading the entirety of the scan chain scan while observing it, chain load data is sliced, apportioning between the different scan chains independently observable sections (slices) of transition data in which all four bit-to-bit transitions (“0” to “0”, “0” to “1”, “1” to 0”, “1” to “1”) are ensured to exist. The remainder of the scan chain load data, which is not observed in the test procedure, can be low-transition data that consumes low dynamic power, such as mostly zeroes or mostly ones.
SCAN TOPOLOGY DISCOVERY IN TARGET SYSTEMS
Topology discovery of a target system having a plurality of components coupled with a scan topology may be performed by driving a low logic value on the data input signal and a data output signal of the scan topology. An input data value and an output data value for each of the plurality of components is sampled and recorded. A low logic value is then scanned through the scan path and recorded at each component. The scan topology may be determined based on the recorded data values and the recorded scan values.
Interfaces for wireless debugging
Existing multi-wire debugging protocols, such as 4-wire JTAG, 2-wire cJTAG, or ARM SWD, are run through a serial wireless link by providing the debugger and the target device with hardware interfaces that include UARTs and conversion bridges. The debugger interface serializes outgoing control signals and de-serializes returning data. The target interface de-serializes incoming control signals and serializes outgoing data. The actions of the interfaces are transparent to the inner workings of the devices, allowing re-use of existing debugging software. Compression, signal combining, and other optional enhancements increase debugging speed and flexibility while wirelessly accessing target devices that may be too small, too difficult to reach, or too seal-dependent for a wired connection.
Instrument noise correction for jitter measurements
A time error vector is determined using pairs of two closest points of input-referred noise data that straddle respective crossing times indicating when a clock signal representation crosses a threshold value, a slew rate of the clock signal representation, and the crossing times. A system filter is applied to the time error vector in the frequency domain. A first RMS value is determined indicating a jitter value present in the filtered time error vector. A raw clock signal time error vector of the clock signal under test is generated, the system filter is applied to the raw clock signal time error vector in the frequency domain, and a second RMS value indicating a jitter content of the filtered raw clock signal time error vector is determined. The second RMS value is corrected using the first RMS value to thereby generate a jitter measurement compensated for input-referred noise.
METHOD AND DEVICE FOR IMPROVING SYNCHRONIZATION IN A COMMUNICATIONS LINK
A data reception device comprises: a first data input for receiving a first data signal and a clock input for receiving a clock signal; and a stability detection circuit adapted to generate: a first error signal indicating when a data transition of the first data signal occurs during a first period at least partially before a first significant clock edge of the clock signal; and a second error signal indicating when a data transition of the first data signal occurs during a second period at least partially after the first significant clock edge of the clock signal; and a control circuit configured to generate a control signal for adjusting the sampling time of the first data signal based on said first and second error signals.
CLOCK JITTER MEASUREMENT CIRCUIT AND SEMICONDUCTOR DEVICE INCLUDING THE SAME
A circuit for measuring clock jitter includes: an internal signal generator configured to generate an internal clock signal and a single pulse signal, respectively synchronized with an input clock signal; a plurality of delay units being connected in series with each other and configured to generate respective delayed clock signals; a plurality of latch circuits configured to latch the single pulse signal in synchronization with the respective delayed clock signals, and output sampling signals; and a count sub-circuit configured to output a count value resulting from counting a number of active sampling signals of the sampling signals.
STUCK-AT FAULT DETECTION ON THE CLOCK TREE BUFFERS OF A CLOCK SOURCE
A first clock signal and second clock signal are generated by first and second clock circuits, respectively. A multiplexer selects between the first clock signal and second clock signal to produce a scan clock signal. A non-scan flip flop clocks a data input through to a data output in response to the second clock signal. A scan chain includes a scan flip flop configured to capture the data output from the non-scan flip flop in response to the scan clock signal. The logic state of the captured data in the scan flip flop of the scan chain is indicative of whether the second clock circuit has a stuck-at fault condition (for example, with respect to any one or more included buffer circuits).