Abstract: Disclosed is a method for testing a memory device, which can test a memory cell block while testing another memory cell block, so as to catch a process defect of the memory device within a short time period, thereby reducing the test time. The method for testing a memory device provided with a bank including N memory cell blocks and sense amplifiers, the method comprising the steps of: a) expressing the N memory cell blocks as a first, a second, . . . , an Nth memory cell block; b) sequentially activating odd-numbered memory cell blocks of the N memory cell blocks one by one in a predetermined time period; c) performing sense, read (or write) and precharge operations for each activated memory cell block; and d) performing steps a) to c) for even-numbered memory cell blocks after tests for all the odd-numbered memory cell blocks are finished.

Abstract: A method for constructing an artificial mark for autonomous driving of an intelligent system, an apparatus and method for determining the location of an intelligent system using the artificial mark, and an intelligent system employing the same.

Abstract: A clock test apparatus for a semiconductor integrated circuit includes a delay unit configured to delay an internal clock signal. A comparison unit compares the phase of an output signal of the delay unit with the phase of a reference clock signal. A phase discrimination unit receives a test mode signal, the reference clock signal, and an output signal of the comparison unit, thereby outputting a discrimination signal.

Abstract: Provided are an apparatus and method of calibrating azimuth of a mobile device. The apparatus includes: a motor; a magnetic field measuring unit disposed in the mobile device and measuring magnetic field data indicating magnitudes of a magnetic field in different directions while being rotated by the motor; and a controller driving the motor, generating a calibration table indicating a correspondence between an actual magnetic field trajectory formed by the magnetic field data and a theoretical magnetic field trajectory and calibrating azimuth of the mobile device using the calibration table.

Abstract: A semiconductor memory device includes a bit line sense amplifier block array, upper and lower unit memory cell arrays and a switching controller. The bit line sense amplifier block array senses and amplifies data of a unit memory cell array. The upper and the lower unit memory cell arrays are respectively connected to upper and lower sides of the bit line sense amplifier block array and store the data in the unit memory cell array. The switching controller selectively connects one of the upper and lower unit memory cell arrays to the bit line sense amplifier block array in response to an active command, and releases the connection when a corresponding one of the upper and lower unit memory cell arrays are not selected but overdriven.

Abstract: A control unit that outputs a plurality of control signals in response to the input of a plurality of counter enable signals allocated into the numerical value of a multiple of 2 is provided. An operating unit increments or decrements by a multiple of 2 in response to input of the plurality of control signals and count up-down signals.

Abstract: A method and apparatus for detecting a free fall of an electronic device. The method includes: sensing a falling acceleration of the electronic device using an acceleration sensor; determining whether the sensed falling acceleration is less than a predetermined threshold; when the sensed falling acceleration is less than the predetermined threshold, determining whether the falling acceleration is a statistical constant, which has a statistical significance, and is maintained for a predetermined time; and when the falling acceleration is a statistical constant and maintained for a predetermined time, determining that the electronic device falls freely. Accordingly, it is possible to exactly detect a free fall of an electronic device, irrespective of an error of the acceleration of gravity generated when a falling acceleration of the electronic device is measured, due to ambient conditions, e.g., a temperature change and a rotation acceleration generated when the electronic device rotates.

Abstract: Disclosed is a method for testing a memory device, which can test a memory cell block while testing another memory cell block, so as to catch a process defect of the memory device within a short time period, thereby reducing the test time. The method for testing a memory device provided with a bank including N memory cell blocks and sense amplifiers, the method comprising the steps of: a) expressing the N memory cell blocks as a first, a second, . . . , an Nth memory cell block; b) sequentially activating odd-numbered memory cell blocks of the N memory cell blocks one by one in a predetermined time period; c) performing sense, read (or write) and precharge operations for each activated memory cell block; and d) performing steps a) to c) for even-numbered memory cell blocks after tests for all the odd-numbered memory cell blocks are finished.

Abstract: Provided is a method of generating a magnetic field map including obtaining magnetic field information, the magnetic field information being information on a magnetic field affecting a mobile body, for each position of the mobile body, and building a magnetic field map based on the magnetic field information for each position of the mobile body. The pose of a mobile body can be statistically checked by the probability obtained using the difference between the magnetic field information observed from the magnetic field map and the actually measured magnetic field information. Although the pose of the mobile body is estimated using a camera that is sensitive to an illumination state where the mobile body is placed, the pose of the mobile body can be relatively accurately checked using the magnetic field map obtained in a situation regardless of illumination, with being less affected by the illumination state where the mobile body is placed. Thus, the pose of the mobile body can be checked with reliability.

Abstract: A semiconductor memory device is provided. The semiconductor memory device includes: an oscillation means for generating a self-refresh enable signal and a self-refresh period pulse having a predetermined period in response to a self-refresh signal; a shift register for generating a self-refresh period level signal maintaining a different level at every self-refresh period defined by the self-refresh enable signal and the self-refresh period pulse, in response to a test mode signal; a multiplexing means for selectively outputting a data signal and the self-refresh period level signal in response to the test mode signal; and an output buffer for buffering the output signal of the multiplexing means to output the buffered signal.

Abstract: Method and system to detect orientations of a moving object using one or more magnetic compasses. The method and system minimize magnetic field interference in a space where an object is moving such that the orientations of the moving object can be precisely detected. The method includes setting one or more earth magnetic field (EMF) conditions without a magnetic field interference component to determine whether the one or more magnetic compasses are located in an EMF area, calculating a magnitude of a magnetic field applied to the moving object using the one or more magnetic field compasses, and detecting an orientation of the moving object by determining whether the calculated magnitude of the magnetic field satisfies the one or more EMF conditions.

Abstract: There are provided a method and apparatus for determining a geomagnetic field by using a compass and a method and apparatus for determining an azimuth angle of a moving object using the method and apparatus for determining a geomagnetic field. The method of determining a geomagnetic field by using a compass includes defining an allowable magnetic field range used to determine a valid geomagnetic region; calculating a magnitude of a magnetic field in a geomagnetic-field validity test region by using a compass; and if the magnitude of the magnetic field is within the allowable magnetic field range, determining that the geomagnetic-field validity test region is the valid geomagnetic region, and if not, determining that there is applied an external magnetic field disturbance. Accordingly, since an error of an azimuth angle of the compass due to an external magnetic field disturbance can be determined, it is possible to accurately detect a valid azimuth angle of the compass.

Abstract: A semiconductor memory device is provided. The semiconductor memory device includes: an oscillation means for generating a self-refresh enable signal and a self-refresh period pulse having a predetermined period in response to a self-refresh signal; a shift register for generating a self-refresh period level signal maintaining a different level at every self-refresh period defined by the self-refresh enable signal and the self-refresh period pulse, in response to a test mode signal; a multiplexing means for selectively outputting a data signal and the self-refresh period level signal in response to the test mode signal; and an output buffer for buffering the output signal of the multiplexing means to output the buffered signal.

Abstract: Provided a method and apparatus for using a magnetic field. The method includes: measuring and storing magnetic field data indicating magnitudes of a magnetic field in different directions at each time by rotating sensors over a space; and checking whether a disturbance of the magnetic field exists, using curve fitting parameters such as amplitude and offset of at least one of magnetic field trajectories formed by the stored magnetic field data.

Abstract: A semiconductor memory device comprises a plurality of cell blocks, block controllers for activating or precharging word lines of each of the cell blocks according to an external active command and a precharge command, a sense amplifier for sensing a fine voltage shared by bit lines and complementary bit lines of the cell blocks, sense amplifier controllers for activating or precharging the sense amplifier according to the external active command and the precharge command, and outputting bit line isolation signals that control the connection between the sense amplifier and the cell block, a block address decoder for decoding external block addresses in normal mode to output a block select signal for selecting one cell block, and outputting a block select signal for selecting even or odd cell blocks according to one of the external block addresses in test mode, and a SES control block for outputting a bit line isolation control signal for controlling the bit line isolation signals and a sense amplifier enable

Abstract: Provided are an apparatus and method of calibrating azimuth of a mobile device. The apparatus includes: a magnetic field measuring unit having a plurality of magnetic sensors aligned in a constant angle interval on the mobile device and measuring magnetic field data indicating magnitudes of a magnetic field in different directions; and a controller generating a calibration table indicating a correspondence between an actual magnetic field trajectory formed by the magnetic field data and a theoretical magnetic field trajectory and calibrating azimuth of the mobile device using the calibration table.

Abstract: The present invention relates to a data pass control device for masking a ringing of a data strobe that occurs when a write operation in a DDR SDRAM is completed. The data pass control device for masking the write ringing in the DDR SDRAM can be advantageously used for masking only a section with the ringing problem during the write operation, so that any unnecessary operations during the write operation can be eliminated and a more stable write operation can be realized by eliminating a write fail.

Abstract: A method and apparatus for detecting a free fall of an electronic device. The method includes: sensing a falling acceleration of the electronic device using an acceleration sensor; determining whether the sensed falling acceleration is less than a predetermined threshold; when the sensed falling acceleration is less than the predetermined threshold, determining whether the falling acceleration is a statistical constant, which has a statistical significance, and is maintained for a predetermined time; and when the falling acceleration is a statistical constant and maintained for a predetermined time, determining that the electronic device falls freely. Accordingly, it is possible to exactly detect a free fall of an electronic device, irrespective of an error of the acceleration of gravity generated when a falling acceleration of the electronic device is measured, due to ambient conditions, e.g., a temperature change and a rotation acceleration generated when the electronic device rotates.

Abstract: A data output control apparatus and method of a semiconductor memory device exactly synchronize the first read data with a clock signal by solving a problem that the first read data is faster than the clock signal as much as a transit time from a voltage level Vddq/2 to a power voltage Vddq or a ground voltage Vssq.

Abstract: A method for constructing an artificial mark for autonomous driving of an intelligent system, an apparatus and method for determining the location of an intelligent system using the artificial mark, and an intelligent system employing the same.