Abstract: A memory module includes a circuit board, a plurality of memory devices, and a power management integrated circuit (PMIC). The circuit board includes first connectors, a second connector, and a third connector connected to an external device. The plurality of memory devices are mounted on the circuit board, and connected to the first connectors. The PMIC receives a first voltage through the second connector, generates a second voltage using the first voltage, and provides the second voltage to the plurality of memory devices The PMIC adjusts the second voltage based on a signal received through the third connector such that a voltage difference of the first voltage and the second voltage is reduced in a training mode of the memory module.

Abstract: A memory module includes a circuit board, a plurality of memory devices, and a power management integrated circuit (PMIC). The circuit board includes first connectors, a second connector, and a third connector connected to an external device. The plurality of memory devices are mounted on the circuit board, and connected to the first connectors. The PMIC receives a first voltage through the second connector, generates a second voltage using the first voltage, and provides the second voltage to the plurality of memory devices The PMIC adjusts the second voltage based on a signal received through the third connector such that a voltage difference of the first voltage and the second voltage is reduced in a training mode of the memory module.

Abstract: A memory module includes semiconductor memory devices, a power management integrated circuit (PMIC), and a control device. The semiconductor memory devices, mounted on a circuit board, operate based on a power supply voltage. The PMIC, mounted on the circuit board, generates the power supply voltage, provides the power supply voltage to the semiconductor memory devices, and stores a trimming control code associated with a minimum level of the power supply voltage when the semiconductor memory devices operate normally in a test mode. During the test mode, the PMIC adjusts a level of the power supply voltage, tests the semiconductor memory devices using the adjusted power supply voltage, and stores the trimming control code based on a result of the test. The control device controls the PMIC based on a first control signal received from an external device.

Abstract: A memory module includes semiconductor memory devices, a power management integrated circuit (PMIC), and a control device. The semiconductor memory devices, mounted on a circuit board, operate based on a power supply voltage. The PMIC, mounted on the circuit board, generates the power supply voltage, provides the power supply voltage to the semiconductor memory devices, and stores a trimming control code associated with a minimum level of the power supply voltage when the semiconductor memory devices operate normally in a test mode. During the test mode, the PMIC adjusts a level of the power supply voltage, tests the semiconductor memory devices using the adjusted power supply voltage, and stores the trimming control code based on a result of the test. The control device controls the PMIC based on a first control signal received from an external device.

Abstract: A semiconductor memory device includes a plurality of chips, a data path that is physically shared by the plurality of chips, a data input/output pad, and a data output driver. The data output driver is configured to receive merged data that includes data merged from a set of chip data read from the plurality of chips, compare the merged data to first reference data in a test mode, compare the merged data to second reference data in a test mode, and based on the comparisons, apply an output voltage at a data input/output pad.

Abstract: A data transceiver system may include an error corrector. The error corrector may include a plurality of delay units, each delay unit being configured to delay a corresponding data signal among a plurality of data signals by a time in response to a corresponding delay code among a plurality of delay codes and outputting the delayed data signal, an error detector configured to receive the plurality of delay codes, determine whether an error has occurred, and output an error signal according to the determination in a data frame lock operation, and a delay controller configured to set initial values of the plurality of delay codes to a predetermined value, vary and output each of the plurality of delay codes in response to a lock signal, and reset initial values the plurality of delay codes in response to the error signal in the data frame lock operation.

Abstract: A test device is provided. The test device includes a first via which transmits a supply voltage, a second via which transmits a ground voltage, a test board including a plurality of test signal vias for transmitting a plurality of test signals, a capacitor disposed on an upper part of the test board and connected between the first via and the second via, and a test socket which electrically connects a device under test (DUT) with the test board. The test socket includes a first region including a flat lower surface bordering the test board, a second region including an uneven lower surface, a plurality of first contactors which are disposed in the first region and which are connected to the plurality of vias, and two second contactors which are disposed in the second region and which are connected to two terminals of the capacitor.

Abstract: A semiconductor memory device includes a plurality of chips, a data path that is physically shared by the plurality of chips, a data input/output pad, and a data output driver. The data output driver is configured to receive merged data that includes data merged from a set of chip data read from the plurality of chips, compare the merged data to first reference data in a test mode, compare the merged data to second reference data in a test mode, and based on the comparisons, apply an output voltage at a data input/output pad.

Abstract: A method and system for testing a semiconductor memory device using low-speed test equipment. The method includes providing a high-frequency test pattern by grouping a command signal and an address signal into command signal groups and address signal groups each corresponding to L cycles of a clock signal output from automatic test equipment (ATE) where L is a natural number. A valid command signal and a valid address signal, which are not in an idle state, are extracted from each of a plurality of command signal groups and each of a plurality of address signal groups. The valid command signal and the valid address signal are compressed into signals having a length corresponding to 1/M (M is a natural number larger than 1) of the cycle of the clock signal where M is a natural number larger than 1. A position designating signal indicating the positions of the valid command signal and the valid address signal in each command signal group and each address signal group is generated.

Abstract: A power-up/power-down detecting circuit may include a power detecting circuit, a selecting circuit, and a determining circuit. The power detecting circuit may generate a plurality of detection signals based on a plurality of sensing signals corresponding to currents flowing through a plurality of function blocks. The selecting circuit may generate a plurality of selection signals. The determining circuit may generate a power-up completion signal and a power-down completion signal. A semiconductor device having the power-up/power-down detecting circuit may determine in real time the power-up time and the power-down time.

Abstract: A test system employing a test controller compressing data, a data compressing circuit and a test method are provided. The test system includes a tester, a device under test (DUT), and a test controller receiving a first clock signal and serial data bits output from the DUT, compressing the serial data bits by m bits (m?4) in response to a second clock signal to generate a signature signal, and outputting the signature signal to the tester. The tester compares a computed signature signal to a 1-bit signature signal to determine whether the DUT is operating poorly or not.

Abstract: Provided are a test pattern generating circuit which generates test patterns having various types and lengths and a semiconductor memory device which performs a test operation using the test pattern generating circuit. The test pattern generating circuit includes a plurality of register blocks which receive test signals input from an external tester through an input/output pad and load the test signals into the resister blocks in synchronization with a low-frequency clock signal; a register block control unit which controls the activation of the register blocks; and an output unit which is connected to the register blocks and outputs the signals loaded into the register blocks as test patterns in synchronization with a high-frequency clock signal.

Abstract: A data transceiver system may include an error corrector. The error corrector may include a plurality of delay units, each delay unit being configured to delay a corresponding data signal among a plurality of data signals by a time in response to a corresponding delay code among a plurality of delay codes and outputting the delayed data signal, an error detector configured to receive the plurality of delay codes, determine whether an error has occurred, and output an error signal according to the determination in a data frame lock operation, and a delay controller configured to set initial values of the plurality of delay codes to a predetermined value, vary and output each of the plurality of delay codes in response to a lock signal, and reset initial values the plurality of delay codes in response to the error signal in the data frame lock operation.

Abstract: An output driver of a semiconductor memory device that operates in a differential mode and in a single mode is disclosed. The output driver includes a current supplying circuit that operates as a resistor in a single mode and as a current source in a differential mode. Accordingly, the semiconductor memory device including the output driver can have high test efficiency, since the number of test pins utilized during a test operation can be selectively reduced for low frequency tests.

Abstract: A test system employing a test controller compressing data, a data compressing circuit and a test method are provided. The test system includes a tester, a device under test (DUT), and a test controller receiving a first clock signal and serial data bits output from the DUT, compressing the serial data bits by m bits (m?4) in response to a second clock signal to generate a signature signal, and outputting the signature signal to the tester. The tester compares a computed signature signal to a 1-bit signature signal to determine whether the DUT is operating poorly or not.

Abstract: A method and system for testing a semiconductor memory device using low-speed test equipment. The method includes providing a high-frequency test pattern by grouping a command signal and an address signal into command signal groups and address signal groups each corresponding to L cycles of a clock signal output from automatic test equipment (ATE) where L is a natural number. A valid command signal and a valid address signal, which are not in an idle state, are extracted from each of a plurality of command signal groups and each of a plurality of address signal groups. The valid command signal and the valid address signal are compressed into signals having a length corresponding to 1/M (M is a natural number larger than 1) of the cycle of the clock signal where M is a natural number larger than 1. A position designating signal indicating the positions of the valid command signal and the valid address signal in each command signal group and each address signal group is generated.

Abstract: A power-up/power-down detecting circuit may include a power detecting circuit, a selecting circuit, and a determining circuit. The power detecting circuit may generate a plurality of detection signals based on a plurality of sensing signals corresponding to currents flowing through a plurality of function blocks. The selecting circuit may generate a plurality of selection signals. The determining circuit may generate a power-up completion signal and a power-down completion signal. A semiconductor device having the power-up/power-down detecting circuit may determine in real time the power-up time and the power-down time.

Abstract: Provided are a test pattern generating circuit which generates test patterns having various types and lengths and a semiconductor memory device which performs a test operation using the test pattern generating circuit. The test pattern generating circuit includes a plurality of register blocks which receive test signals input from an external tester through an input/output pad and load the test signals into the resister blocks in synchronization with a low-frequency clock signal; a register block control unit which controls the activation of the register blocks; and an output unit which is connected to the register blocks and outputs the signals loaded into the register blocks as test patterns in synchronization with a high-frequency clock signal.

Abstract: An output driver of a semiconductor memory device that operates in a differential mode and in a single mode is disclosed. The output driver includes a current supplying circuit that operates as a resistor in a single mode and as a current source in a differential mode. Accordingly, the semiconductor memory device including the output driver can have high test efficiency, since the number of test pins utilized during a test operation can be selectively reduced for low frequency tests.