Abstract: A memory module is provided which includes a printed circuit board; first semiconductor packages provided on one surface of the printed circuit board; and second semiconductor packages provided on the other surface of the printed circuit board, the first semiconductor packages and the second semiconductor packages having semiconductor dies that form ranks. A number of the ranks formed by the first semiconductor packages being different from a number of the ranks formed by the second semiconductor packages. Semiconductor packages forming a same one of the ranks receive a chip selection signal in common and semiconductor packages forming other ranks receive a different chip selection signal.

Abstract: A memory module comprises a plurality of semiconductor memory devices each comprising a mode register set (MRS) circuit configured to generate an enable signal corresponding to an error mode of the semiconductor memory device in response to an MRS command received from a command decoder, and an address buffer configured to store a predetermined address signal, to receive an address signal and corresponding data from an external device, and to compare the address signal received with the predetermined address signal in response to the enable signal. As a consequence of determining that the address signal received from the external device is the same as the predetermined address signal stored in the address buffer, data different from the corresponding data received from the external device is written to a memory cell corresponding to the predetermined address signal.

Abstract: A memory module is provided which includes a printed circuit board; first semiconductor packages provided on one surface of the printed circuit board; and second semiconductor packages provided on the other surface of the printed circuit board, the first semiconductor packages and the second semiconductor packages having semiconductor dies that form ranks. A number of the ranks formed by the first semiconductor packages being different from a number of the ranks formed by the second semiconductor packages. Semiconductor packages forming a same one of the ranks receive a chip selection signal in common and semiconductor packages forming other ranks receive a different chip selection signal.

Abstract: A semiconductor module includes a plurality of module pins and a semiconductor device. Module pins receive an identification pattern signal having M bits and outputs a test identification pattern, where M is a positive integer. The semiconductor device includes device pins, and outputs the identification pattern signal through the device pins in response to a connection identification control signal for identifying a configuration of pin connections between the module pins and the device pins. The semiconductor module effectively identifies a configuration of pin connections between the module pins and the device pins.

Abstract: A memory module that includes: a printed circuit board having a connecting terminal; memory chips arranged on the printed circuit board; data buffers disposed on a first surface of the printed circuit board and corresponding to the memory chips; and resistance units disposed on a second surface of the printed circuit board and corresponding to the data buffers.

Abstract: A memory module comprises a plurality of semiconductor memory devices each comprising a mode register set (MRS) circuit configured to generate an enable signal corresponding to an error mode of the semiconductor memory device in response to an MRS command received from a command decoder, and an address buffer configured to store a predetermined address signal, to receive an address signal and corresponding data from an external device, and to compare the address signal received with the predetermined address signal in response to the enable signal. As a consequence of determining that the address signal received from the external device is the same as the predetermined address signal stored in the address buffer, data different from the corresponding data received from the external device is written to a memory cell corresponding to the predetermined address signal.

Abstract: A memory module is provided which includes a printed circuit board; first semiconductor packages provided on one surface of the printed circuit board; and second semiconductor packages provided on the other surface of the printed circuit board, the first semiconductor packages and the second semiconductor packages having semiconductor dies that form ranks. A number of the ranks formed by the first semiconductor packages being different from a number of the ranks formed by the second semiconductor packages. Semiconductor packages forming a same one of the ranks receive a chip selection signal in common and semiconductor packages forming other ranks receive a different chip selection signal.

Abstract: A memory module including a plurality of ranks. Each of the ranks includes a parallel test apparatus for simultaneous testing and a parallel test control unit. In response to a parallel test mode control signal, the parallel test apparatus generates first parity data for write data including a plurality of bits and generating first data obtained by replacing a bit value of at least one bit of the plurality of bits of the write data with the first parity data during a write operation, and generates second parity data for the first data and transmitting the second parity data as read data during a read operation. The parallel test control unit controls the write operation and the read operation in a parallel test mode by generating the parallel test mode control signal. Combinations of read data from the plurality of ranks correspond to different bits of the write data.

Abstract: A semiconductor module includes a plurality of module pins and a semiconductor device. Module pins receive an identification pattern signal having M bits and outputs a test identification pattern, where M is a positive integer. The semiconductor device includes device pins, and outputs the identification pattern signal through the device pins in response to a connection identification control signal for identifying a configuration of pin connections between the module pins and the device pins. The semiconductor module effectively identifies a configuration of pin connections between the module pins and the device pins.

Abstract: A test board includes a plurality of test modules. Each test module stores a first control signal, a data signal, and a second control signal in response to a clock signal, and tests a corresponding device under test (DUT) using the first control signal and the stored data signal in response to the second control signal to generate an error signal indicating whether the DUT is defective. Each test module outputs the first control signal, the data signal, and the second control signal to a test module in a next stage, and each test module of a subsequent stage receives the error signal stored generated by a test module in a previous stage in response to the clock signal.

Abstract: A method of accelerating write timing calibration and a write timing calibration acceleration circuit in a semiconductor memory device are disclosed. The write timing calibration acceleration circuit includes a phase difference detection unit and a detection data output unit. The phase difference detection unit detects a phase difference between a first signal and a second signal applied for a write timing calibration. The detection data output unit outputs detection data corresponding to the detected phase difference through a data output line. According to the write timing calibration acceleration circuit of the inventive concept, a time taken to perform a write timing calibration is reduced, thereby minimizing boot up time and power consumption.

Abstract: A memory module including a plurality of ranks. Each of the ranks includes a parallel test apparatus for simultaneous testing and a parallel test control unit. In response to a parallel test mode control signal, the parallel test apparatus generates first parity data for write data including a plurality of bits and generating first data obtained by replacing a bit value of at least one bit of the plurality of bits of the write data with the first parity data during a write operation, and generates second parity data for the first data and transmitting the second parity data as read data during a read operation. The parallel test control unit controls the write operation and the read operation in a parallel test mode by generating the parallel test mode control signal. Combinations of read data from the plurality of ranks correspond to different bits of the write data.

Abstract: A test board includes a plurality of test modules. Each test module stores a first control signal, a data signal, and a second control signal in response to a clock signal, and tests a corresponding device under test (DUT) using the first control signal and the stored data signal in response to the second control signal to generate an error signal indicating whether the DUT is defective. Each test module outputs the first control signal, the data signal, and the second control signal to a test module in a next stage, and each test module of a subsequent stage receives the error signal stored generated by a test module in a previous stage in response to the clock signal.