Semiconductor device having a boundary scan test circuit
AssigneeNEC Corporation
InventorHirokazu Danbayashi
Life of this patent
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AssigneeNEC Corporation
InventorHirokazu Danbayashi
Estimating the term…
A boundary scan test circuit comprises a plurality of register cells correspondingly to external pins of a semiconductor device, the register cells being coupled together to form a shift register during a test operation mode. The register cells includes a first selector for selecting one of a parallel input data, serial input data and a code signal, a first register for latching the output of the first selector to output a serial data to be input to a succeeding register cell, a second register for latching the output of the first selector, a second selector for selecting the parallel data or the output of the second register to output parallel data. The code signal is determined based on corresponding one of bits of ID code of the semiconductor device. The ID code is output from the register cells without providing an ID code register, resulting in a simple construction of the register cells and a reduced chip area for the semiconductor device.
A semiconductor device comprising an internal logic circuit, a plurality of external pins and a boundary scan test circuit including a plurality of boundary scan register cells each disposed correspondingly to associated one of said external pins for transmitting parallel data between said internal logic circuit and said associated one of said external pins, said boundary scan register cells being electrically connected to each other responsive to an external signal to form a shift register for transmitting serial data, each of said boundary scan register cells comprising:
A semiconductor device comprising an internal logic circuit, a plurality of external pins and a boundary scan test circuit including a plurality of boundary scan register cells each disposed correspondingly to associated one of said external pins for transmitting parallel data between said internal logic circuit and associated one of said external pins, said boundary scan register cells being electrically connected to each other responsive to a first external signal to form a shift register for transmitting serial data, each of said boundary scan register cells comprising:
Dependencies are inferred from the claim text.