摘要:
In one aspect, an electronic device that has been partitioned into segments by using clock gating or signal gating is tested. One of the segments that is a source of a failure is identified. Diagnostic procedures are applied to the identified segment to determine a cause of the failure.
摘要:
In one aspect, an electronic device that has been partitioned into segments by using clock gating or signal gating is tested. One of the segments that is a source of a failure is identified. Diagnostic procedures are applied to the identified segment to determine a cause of the failure.
摘要:
In a first aspect, a first method is provided for isolating a defect in a scan chain. The first method includes the steps of (1) modifying a first test mode of one or more of a plurality of latches included in the scan chain; (2) operating the one or more latches whose first test modes are modified in the modified first test mode; and (3) operating one or more of the plurality of latches included in the scan chain in a second test mode. Numerous other aspects are provided.
摘要:
Systems, methods and apparatus are provided for isolating a defect in a scan chain. The invention includes modifying a first test mode of a plurality of latches included in a scan chain, operating the latches in the modified first test mode, and operating the plurality of latches included in the scan chain in a second test mode. A portion of the scan chain adjacent and following a stuck-@-0 or stuck-@-1 fault in the scan chain may store and/or output a value complementary to the value on the output of the previous portion of the scan chain due to the fault. Such values may be unloaded from the scan chain and used for diagnosing (e.g., isolating a defect in) the defective scan chain. Numerous other aspects are provided.
摘要:
A system and method for testing first and second sets of electronic devices on a microchip is provided. The first set of devices receive input data and then send output data to a first multiple input shift register (MISR). The second set of devices receiving input data and then sending output data to a second MISR. The method includes determining a first seed signature value associated with the first MISR that induces the first MISR to have a first final signature value comprising a plurality of identical binary values when the first set of devices send valid output data to the first MISR when receiving a first predetermined sequence of input data. The method further includes determining a second seed signature value associated with the second MISR that induces the second MISR to have a second final signature value comprising a plurality of identical binary values when the second set of devices send valid output data to the second MISR when receiving a second predetermined sequence of input data. The method further includes initializing first and second states of the first MISR and the second MISR, respectively, to the first and second signature values, respectively. The method further includes inputting the first and second predetermined sequences of input data to the first and second set of devices, respectively, and generating first and second final signatures values from output data received from the first and second set of devices, respectively. Finally, the method includes indicating that the first and second set of devices have failed testing when at least one of the plurality of binary values in the first and second final signature values are not identical.
摘要:
A soft-fuse test algorithm is distributed on-chip from an ABIST engine through an LSSD shift register chain to dynamically evaluate a plurality of arrays with redundancy compensation for bad elements and repair those that are fixable. Each arrays outputs are monitored by a different multiple input signature register (MISR) with an initial data pattern seed that provides a final desired state of the MISR with either all “0”s or all “1”s, allowing for a simple “single-bit” MISR error evaluation of the monitored array. Using the above single-bit MISR error evaluation technique an ABIST test sequence is executed concurrently on all arrays through the shift register chain. If any arrays are in error, redundancy compensation is employed and the ABIST test is repeated for all possible array redundant combinations until a functional configuration for each array is identified or all possible redundant combinations have been tried. Once functioning array configurations are verified, the associated soft-fuse states can be used to blow fuses and/or extracted for further system setup, permanent fuse-blowing and yield analysis. Multiple shift register chains driven by separate ABIST engines may be required to test all arrays on a chip.
摘要:
A method for constructing a secure Internet transaction, the method includes: receiving a user identification (userid) and user password on a client device for filling out a form generated by a secure web site; concatenating the user's Internet Protocol (IP) address with a separate password that is maintained on the secure web site that the user is authenticating to; encrypting the concatenated user IP and separate password to form an Internet Protocol password (IPPW); wherein the encrypting is carried out with a client device linear feedback shift register (LFSR) with a defined cycle count; building a transaction consisting of the IPPW, defined cycle count, and userid; transmitting the transaction and form via a network towards the secure web site; wherein in response the secure website performs the following: decrypts the IPPW, and determines if the IP portion of the decrypted IPPW is equal to the user's IP address.
摘要:
A method for tracking paper currency in a holder, includes: scanning paper currency deposited or removed from a holder; determining the total number of each individual denomination of paper currency contained within the holder based on the scanned paper currency deposited and removed from the holder; recording the total number of each individual denomination of paper currency; determining the total value of the paper currency within the holder; outputting the denomination of paper currency when the paper currency is scanned during depositing or removal from the holder; outputting the recorded number of each individual denomination of paper currency and the total value of the currency within the holder; and wherein the recorded number of each individual denomination of paper currency and the total value of the currency within the holder is dynamically tabulated based on the scanning of paper currency deposited or removed from the holder.
摘要:
Methods for testing a semiconductor circuit (10) including testing the circuit and modifying a well bias (14, 18) of the circuit during testing. The methods improve the resolution of voltage-based and IDDQ testing and diagnosis by modifying well bias during testing. In addition, the methods provide more efficient stresses during stress testing. The methods apply to ICs where the semiconductor well (wells and/or substrates) are wired separately from the chip VDD and GND, allowing for external control (40) of the well potentials during test. In general, the methods rely on using the well bias to change transistor threshold voltages.
摘要:
An authentication method and system. A computing system generates an authentication table associated with a user. The computing system receives first authentication data and second authentication data differing from the first authentication data. The first authentication data and the second authentication data are placed in the authentication table. The authentication table comprising the first authentication data and the second authentication data is stored in the computing system. The computing system generates an action table. The computing system receives first action data and second action data and places the first action data and the second action data in the action table. The action table comprising the first action data and the second action data is stored in the computing system.