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 disclosure describes novel methods and apparatuses for accessing test compression architectures (TCA) in a device using either a parallel or serial access technique. The serial access technique may be controlled by a device tester or by a JTAG controller. Further the disclosure provides an approach to access the TCA of a device when the device exists in a daisy-chain arrangement with other devices, such as in a customer's system. Additional embodiments are also provided and described in the disclosure.

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 disclosure describes a novel method and apparatus for improving interposers that connected stacked die assemblies to system substrates. The improvement includes the addition of IEEE 1149.1 circuitry within interposers to allow simplifying interconnect testing of digital and analog signal connections between the interposer and system substrate it is attached too. The improvement also includes the additional 1149.1 controlled circuitry that allows real time monitoring of voltage supply and ground buses in the interposer. The improvement also includes the additional of 1149.1 controlled circuitry that allows real time monitoring of functional digital and analog input and output signals in the interposer. The improvement also provides the ability to selectively serially link the 1149.1 circuitry in the interposer with 1149.1 circuitry in the die of the stack.

The disclosure describes a novel method and apparatus for making device TAPs addressable to allow device TAPs to be accessed in a parallel arrangement without the need for having a unique TMS signal for each device TAP in the arrangement. According to the disclosure, device TAPs are addressed by inputting an address on the TDI input of devices on the falling edge of TCK. An address circuit within the device is associated with the device's TAP and responds to the address input to either enable or disable access of the device's TAP.

The disclosure describes a novel method and apparatus for improving interposers that connected stacked die assemblies to system substrates. The improvement includes the addition of IEEE 1141.1 circuitry within interposers to allow simplifying interconnect testing of digital and analog signal connections between the interposer and system substrate it is attached too. The improvement also includes the additional 1141.1 controlled circuitry that allows real time monitoring of voltage supply and ground buses in the interposer. The improvement also includes the additional of 1141.1 controlled circuitry that allows real time monitoring of functional digital and analog input and output signals in the interposer. The improvement also provides the ability to selectively serially link the 1141.1 circuitry in the interposer with 1141.1 circuitry in the die of the stack.

A scan flip-flop includes a multiplexer, a first latch, a second latch, an output buffer and a clock buffer. The multiplexer selects one of a data input signal and a scan input signal based on an operation mode. The first latch latches an output of the multiplexer. The second latch latches an output of the first latch. The output buffer generates an output signal based on an output of the second latch. The clock buffer generates a first clock signal and a second clock signal that control operation of the first latch and the second latch. The first latch, the second latch, and the clock buffer are sequentially arranged along a first direction. A first clock line supplying the first clock signal and a second clock line supplying the second clock signal have a cross couple connection.

The present disclosure provides a multi-core processor. The multi-core processor comprises a plurality of cores and a debug circuit, the debug circuit comprising debug circuits in the same number as that of the cores, transmission controllers in the same number as that of the cores, and a master control circuit, each of the debug circuits being connected to one core and one transmission controller, respectively, and all transmission controllers being connected to the master control circuit. Each of the debug circuits is configured to generate a debug event signal and respond to the generated debug event signal or received debug event signals generated by other debug circuits. Each of the transmission controllers is configured to respectively control transmission of the debug event signal between the respectively connected debug circuit and the master control circuit. The master control circuit is configured to forward debug event signals among different transmission controllers. The present disclosure can realize rapid configuration and control of debug event signal transmission, and at the same time lower power consumption of a debug circuit.

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 a test architecture that supports a common approach to testing individual die and dies in a 3D stack arrangement. The test architecture uses an improved TAP design to facilitate the testing of parallel test circuits within the die.