Patent application number | Description | Published |
20080204094 | Semiconductor memory device and method for driving the same - The present invention intends to provide a semiconductor memory device including a delay locked loop (DLL) circuit capable of generating a duty-corrected delay locked clock. A semiconductor memory device includes: a DLL circuit for generating a delay locked clock through a delay locked operation; and a duty-correction circuit for correcting a duty ratio of the delay locked clock by using the delay locked clock and a divided clock generated by dividing the delay locked clock by an even value. | 08-28-2008 |
20080204099 | Clock generator and clock duty cycle correction method - A clock duty cycle correction (DCC) circuit for correcting a clock duty cycle of an external clock includes a phase comparator for comparing a phase of a rising clock with that of a falling clock to thereby output comparing signal; a DCC controller for outputting a DCC enable signal and a weight selection signal in response to the comparing signal and a first and a second lock state signal; a DCC mixing block for blending the rising clock and the falling clock in response to the DCC enable signal and the weight selection signal to thereby generate a rising and a falling pre-clock signals; and a clock selector for selectively output the rising and the falling pre-clock signals in response to the weight selection signal. | 08-28-2008 |
20080239848 | SEMICONDUCTOR MEMORY DEVICE AND METHOD FOR DRIVING THE SAME - A semiconductor memory device includes a write driver, a first precharging unit, and a second precharging unit. The write driver loads data applied to a first data line onto a second data line. The first precharging unit precharges the second data line to a precharging voltage in response to a precharging signal. The second precharging unit overdrives the second data line to a voltage higher than the precharging voltage in response to an overdriving signal enabled for a predetermined time period during an initial precharging interval of the second data line. | 10-02-2008 |
20090006912 | Semiconductor memory device having burn-in test mode and method for driving the same - A semiconductor memory device includes: a pattern selector configured to receive a first test control signal and a second test control signal to output a plurality of pattern selection signals and a selection end signal in response to an entry signal; a shifting controller configured to receive the first test control signal and the second test control signal to output a shifting control signal in response to the selection end signal; and a pattern test signal generator configured to select a stress pattern corresponding to the pattern selection signals to generate a plurality of test mode signals for controlling a sequential entry into a plurality of test modes for executing the stress pattern in response to the shifting control signal. | 01-01-2009 |
20090045858 | DELAY LOCKED LOOP CIRCUIT - A delay locked loop (DLL) circuit for a synchronous dynamic random access memory (SDRAM) is provided. If a locking state is broken due to an external change such as a change of tCK or power supply voltage, indicating that a delay of a delay replication modeling unit involved in a DRAM is abruptly changed, the locking state can be recovered within a certain time, e.g., 200 tCK, by creating an internal reset signal in the DLL circuit by a circuit that monitors the state and then conducting a phase update using a rough delay value. | 02-19-2009 |
20090219775 | Semiconductor memory device - Semiconductor memory device includes a cell array including a plurality of unit cells; and a test circuit configured to perform a built-in self-stress (BISS) test for detecting a defect by performing a plurality of internal operations including a write operation through an access to the unit cells using a plurality of patterns during a test procedure carried out at a wafer-level. | 09-03-2009 |
20090231933 | SEMICONDUCTOR MEMORY DEVICE WITH SIGNAL ALIGNING CIRCUIT - A signal aligning circuit includes a plurality of pads receiving input signals in parallel 1 bit by 1 bit; a first transferring unit for transferring the input signals as first signals in synchronization with a first clock signal of an internal clock, and transferring the input signals as second signals in synchronization with a second clock signal of the internal clock; a second transferring unit for transferring the first signals in synchronization with the second clock signal of the internal clock; and an aligning unit for aligning the first and second signals transferred from the first and second transferring units and outputting the aligned signal as output signals. | 09-17-2009 |
20090290436 | TEST CIRCUIT FOR MULTI-PORT MEMORY DEVICE - A semiconductor memory device includes a read bus line for transferring read data; a write bus line for transferring write data; and a temporary data storage unit connected between the read bus line and the write bus line and controlled by a test mode signal enabled during a test mode. | 11-26-2009 |
20100169583 | MULTI-PORT MEMORY DEVICE WITH SERIAL INPUT/OUTPUT INTERFACE - A multi-port memory device includes ports, banks, a global data bus, an input/output (I/O) controller, mode register set (MRS), a clock generator, and a test I/O controller. The I/O controller transmits a test signal to the global data bus in response to a mode register enable signal. The MRS generates a test enable signal in response to the mode register enable signal and outputs a mode selection signal which determines a data transmission mode of a test I/O signal in response to the test signal. The clock generator receives an external clock and generates an internal clock based on the external clock in response to the mode selection signal. The test I/O controller inputs/outputs the test I/O signal in synchronism with the internal clock. The mode register enable signal active during a test operation mode for testing a core area of the banks. | 07-01-2010 |
20110026342 | MULTI-PORT MEMORY DEVICE - A multi-port memory device includes: a bank having a plurality of matrices; a plurality of test data input/output units where data is input/output using a test mode for detecting a defective memory cell; a plurality of ports converted into a decoding device for decoding a command/address at the test mode; a plurality of data transfer lines for transferring data between the matrices and the test data I/O units, wherein the data transfer lines is grouped into the number of matrices; and a plurality of temporary storing units included between the data transfer lines and the matrices for temporarily storing data. | 02-03-2011 |
20110231717 | SEMICONDUCTOR MEMORY DEVICE - Semiconductor memory device includes a cell array including a plurality of unit cells; and a test circuit configured to perform a built-in self-stress (BISS) test for detecting a defect by performing a plurality of internal operations including a write operation through an access to the unit cells using a plurality of patterns during a test procedure carried out at a wafer-level. | 09-22-2011 |