Abstract: There is provided a memory device in which memory cells may be tested using several different test data patterns. The memory device may include a switch unit, a plurality of storage units, and a selector. The switch unit may transfer bits of data received in response to a mode control signal to memory cells or transfers bits of test data to the memory cells. The plurality of storage units respectively stores bits of test data in response to bits of an input control signal. The selector applies test data stored in one of the storage units to the switch unit in response to the input control signal.

Abstract: A test mode setting method and circuit that reduce the number of signal lines, thereby minimizing the number of wires of a semiconductor memory device. The method includes: sequentially activating a plurality of selection signals; when each selection signal is activated, activating one of a plurality of test mode addresses corresponding to the activated selection signal; when the last one of the selection signals is activated, and one of the test mode addresses corresponding to the last selection signal is activated, activating a test mode corresponding to the activated test mode address.

Abstract: Embodiments of the invention provide a semiconductor memory device. In one embodiment, the invention provides a semiconductor memory device comprising a first row of pads comprising a first plurality of data input/output pads; a second row of pads comprising a second plurality of data input/output pads; and a first input/output multiplexer associated with the first row of pads and adapted to provide first output data only to at least one data input/output pad of the first row of pads, even after a data input/output mode of the semiconductor memory device has changed. The semiconductor memory device further comprises a second input/output multiplexer associated with the second row of pads and adapted to provide second output data only to at least one data input/output pad of the second row of pads, even after the data input/output mode has changed.

Abstract: Provided is a synchronous semiconductor memory device with improved latency control. In one embodiment, the synchronous semiconductor memory device may include a clock synchronizing circuit, a latency circuit, and a latency control circuit. The clock synchronizing circuit may receive an external clock signal and output a data output clock signal. The latency circuit may store a read signal in response to at least one sampling clock signal, generate a plurality of clock control signals in a sequential manner, generate a plurality of transfer clock signals synchronized with the plurality of clock control signals, and supply a latency signal in response to the transfer clock signals. The latency control circuit may delay the plurality of clock control signals by the sum of output delay time and the read command delay time so as to generate a plurality of sampling clock signals synchronized with the plurality of delayed clock control signals.

Abstract: A semiconductor test circuit is installed inside a semiconductor device to measure the state of at least one electrical signal of the semiconductor device, and includes first, second, and Nth signal selecting units (where N is an integer greater than 2). The first signal selecting unit either outputs a first electrical signal received from a first terminal or provides a high impedance state to a pad connected to a second terminal in response to a first control signal. The second signal selecting unit either outputs a second electrical signal received from a first terminal or provides a high impedance state to the pad connected to a second terminal in response to a second control signal. The Nth signal selecting unit either outputs an Nth electrical signal (N is an integer) received from a first terminal or provides a high impedance state to the pad connected to the second terminal in response to an Nth control signal.

Abstract: There is provided a memory device in which memory cells may be tested using several different test data patterns. The memory device may include a switch unit, a plurality of storage units, and a selector. The switch unit may transfer bits of data received in response to a mode control signal to memory cells or transfers bits of test data to the memory cells. The plurality of storage units respectively stores bits of test data in response to bits of an input control signal. The selector applies test data stored in one of the storage units to the switch unit in response to the input control signal.

Abstract: A semiconductor test circuit operates without a predetermined delay time and is capable of selecting an electrical signal to be tested even after assembly of a semiconductor device has been completed. The semiconductor test circuit is installed inside the semiconductor device to measure the state of at least one electrical signal of the semiconductor device. The semiconductor test circuit includes first, second, . . . , and Nth signal selecting units (where N is an integer greater than 2). The first signal selecting unit either outputs a first electrical signal received from a first terminal or provides a high impedance state to a pad connected to a second terminal in response to a first control signal. The second signal selecting unit either outputs a second electrical signal received from a first terminal or provides a high impedance state to the pad connected to a second terminal in response to a second control signal.

Abstract: A semiconductor memory device to which information of different data bits can be written, and a method of electrically testing the semiconductor memory device are provided. In a mode for testing a memory cell array of the semiconductor memory device, the semiconductor memory comprises a control signal generation pad capable of writing non-identical data to data input/output pads of each group when data is written to the memory cell array.

Abstract: Provided are a circuit and a method for transforming a data input/output format of a semiconductor memory device which is capable of generating various types of data patterns when the number of memory cells connected to one column selection line is greater than the number of data input pins. The circuit for transforming a data input/output format of a semiconductor memory device includes a first transmission circuit, a second transmission circuit, and a mode register set (MRS). The first transmission circuit is activated when a first test mode signal is enabled, receives n data inputs from n data input ends, and transmits the n data inputs to m memory cells. Here, n and m are natural numbers and m is greater than n. The second transmission circuit is activated when a second test mode signal is enabled, receives n data inputs from the n data input ends, and transmits the n data inputs to the m memory cells.

Abstract: Provided are a circuit and a method for transforming a data input/output format of a semiconductor memory device which is capable of generating various types of data patterns when the number of memory cells connected to one column selection line is greater than the number of data input pins. The circuit for transforming a data input/output format of a semiconductor memory device includes a first transmission circuit, a second transmission circuit, and a mode register set (MRS). The first transmission circuit is activated when a first test mode signal is enabled, receives n data inputs from n data input ends, and transmits the n data inputs to m memory cells. Here, n and m are natural numbers and m is greater than n. The second transmission circuit is activated when a second test mode signal is enabled, receives n data inputs from the n data input ends, and transmits the n data inputs to the m memory cells.

Abstract: A semiconductor memory device including a delay locked loop (DLL) that is capable of turning off the DLL in a precharge mode while maintaining locking information stored before the DLL operates in the precharge mode is provided. The DLL includes an ON/OFF mode for turning the DLL on or off. The DLL also includes a standby mode for turning the DLL off while still maintaining locking information stored before the DLL operates in a precharge mode in response to the activation of a standby enabling signal. The standby enabling signal is inactive when the DLL locks. The standby enabling signal is active when DLL lock is complete.

Abstract: A semiconductor memory device including a delay locked loop (DLL) that is capable of turning off the DLL in a precharge mode while maintaining locking information stored before the DLL operates in the precharge mode is provided. The DLL includes an ON/OFF mode for turning the DLL on or off. The DLL also includes a standby mode for turning the DLL off while still maintaining locking information stored before the DLL operates in a precharge mode in response to the activation of a standby enabling signal The standby enabling signal is inactive when the DLL locks. The standby enabling signal is active when DLL lock is complete.

Abstract: A delay locked loop circuit includes a variable delay circuit that receives an input clock signal and produces a delayed clock signal that is variably delayed with respect to the input clock signal responsive to a delay control signal applied to the variable delay circuit. A delay control circuit is responsive to the input clock signal and to the delayed clock signal, and applies a delay control signal to the variable delay circuit based on a comparison of an edge of the delayed clock signal corresponding to a first edge of the input clock signal to a second edge of the input clock signal that follows the first edge of the input clock signal. In an embodiment, the delay control circuit includes a phase comparator circuit that receives the input clock signal and the delayed clock signal and produces a phase comparison signal that indicates whether the edge of the delayed clock signal corresponding to the first edge of the reference clock signal leads or lags the second edge of the input clock signal.

Abstract: Integrated circuit devices having synchronized signal generators therein include a first signal generator and a second signal generator. The first signal generator receives a first input signal and a complementary version of the first input signal at true and complementary inputs thereto, respectively, and generates a first output signal having a leading edge in-sync with a leading edge of the first input signal (e.g., clock signal CLK) but delayed relative thereto by a first time interval. The second signal generator receives the first input signal and the complementary version of the first input signal at complementary and true inputs thereto, respectively, and generates a second output signal having a leading edge in-sync with a leading edge of the complementary version of the first input signal but delayed relative thereto by the first time interval. First and second pulse generators are also preferably provided.