The exemplary embodiments of the present invention provides a scan cluster reordering method and apparatus which perform a scan correlation aware scan cluster reordering to reduce a power generated during the scan test and place scan cells having a high correlation to be adjacent to each other by analyzing the correlation between scan cells, and reduce a test power generated during the scan test.

A system includes a test access port (TAP) configured to provide internal joint test action group (IJTAG) access to one or more test data registry (TDR). The system further includes a plurality of hierarchical electronic components, wherein each hierarchical electronic component includes a de-asserted segment inserted bit (D-SIB) register, an asserted segment inserted bit (A-SIB) register, and a TDR associated with the D-SIB register. Each D-SIB register is configured to prevent access to its associated TDR when a reset signal is asserted and each A-SIB register is configured to provide access to its subsequent A-SIB register or D-SIB register coupled thereto when the reset signal is asserted.

A method of updating firmware in a chip in a stable and effective manner receives firmware outputted by a controller. The received firmware is burned into the chip. A voltage level of a controlling signal outputted by a controlling pin of the chip is latched to a certain level based on a latching signal at a first voltage level outputted by the controller. The storage medium is refreshed for making the burned firmware effective based on refresh instruction outputted by the controller. The latching signal at a second voltage level for unlatching the voltage level of the controlling signal is outputted by the controller if operations of the chip are stable. An updating operation of the chip by the method does not interrupt other operations being executed by the chip. A firmware updating apparatus and a computer readable storage medium applying the method are also disclosed.

An electronic device includes a processing unit with a memory, a JTAG interface with test-data-input and test-mode-select lines coupled to the processing unit, a bridge circuit, and a multiplexer circuit. The bridge circuit includes a serial communication interface receiving a serial data input signal which conveys an input serial data frame. The bridge circuit includes a serial-to-parallel converter circuit block receiving the input serial data frame, processing the input serial data frame to read first and second subsets of input binary values therefrom, and transmitting the first subset via a first output signal and the second subset via a second output signal. The multiplexer circuit selectively propagates a received test-data-input signal or the first output signal to the test data input line, and selectively propagates a test-mode-select signal or the second output signal to the test mode select line of the JTAG interface.

A method of updating firmware in a chip in a stable and effective manner receives firmware outputted by a controller. The received firmware is burned into the chip. A voltage level of a controlling signal outputted by a controlling pin of the chip is latched to a certain level based on a latching signal at a first voltage level outputted by the controller. The storage medium is refreshed for making the burned firmware effective based on refresh instruction outputted by the controller. The latching signal at a second voltage level for unlatching the voltage level of the controlling signal is outputted by the controller if operations of the chip are stable. An updating operation of the chip by the method does not interrupt other operations being executed by the chip. A firmware updating apparatus and a computer readable storage medium applying the method are also disclosed.

An integrated circuit (IC) device and a method for communicating test data utilizes test control circuitry, and a test controller. The test controller is coupled with the test control circuitry and decodes packetized test pattern data to identify configuration data for the test controller and test data for the test control circuitry. The test controller further communicates the test data to the test control circuitry, and packetizes resulting data received from the test control circuitry. The resulting data corresponds to errors identified by a test performed based on the test pattern data.

A method of loading a data string into a Joint Test Action Group (JTAG) shift register is provided. The method includes determining whether the last bit of the data string is equal to one or zero. In response to determining that the last bit is equal to one, the method includes simultaneously setting each flip-flop of the shift register to one, identifying first data string loading bits by removing, from the data string, the last bit and any other bits in a continuous sequence of bits, including the last bit, that are each equal to one, and sequentially loading the identified first data string loading bits into the shift register. A testing apparatus for performing the method and an enhanced JTAG interface are also provided. The method, testing apparatus, and enchanced JTAG interface may reduce the number of clock cycles required to load the shift register.

Testing of die on wafer is achieved by; (1) providing a tester with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuitry, (2) providing die on wafer with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuity, and (3) providing a connectivity mechanism between the bidirectional transceiver circuitry's of the tester and a selected group or all of the die on wafer for communication of the JTAG signals.

This disclosure describes die test architectures that can be implemented in a first, middle and last die of a die stack. The die test architectures are mainly the same, but for the exceptions mentioned in this disclosure.

The first logic wafer is attached to a supporting wafer, which adds sufficient depth to this bonded structure such that the first logic wafer may be thinned during the manufacturing process. The first logic wafer is thinned such that the through silicon vias may be etched in the substrate of the first logic wafer so as to provide adequate connectivity to a second logic wafer, which is bonded to the first logic wafer. The second logic wafer adds sufficient depth to this bonded structure to allow the supporting wafer to then be thinned to enable through silicon vias to be added to the supporting wafer so as to provide appropriate connectivity for the entire stacked structure. The thinned supporting wafer is retained in the finished stacked wafer structure and may comprise additional components (e.g. capacitors) supporting the operation of the processing circuitry in the logic wafers.