Abstract:
Provided are a waveguide structure and an arrayed waveguide grating structure. The arrayed waveguide grating structure includes an input star coupler, an output star coupler, and a plurality of arrayed waveguides optically connecting the input star coupler and the output star coupler. Each of the arrayed waveguides includes at least one section having a high confinement factor and at least two sections having a relatively low confinement factor. The sections of the arrayed waveguides having a high confinement factor have the same structure.
Abstract:
A non-volatile memory device includes a feedback circuit and a precharge switching transistor. The feedback circuit generates a feedback signal based on a voltage level of a bitline during a precharge operation. The precharge switching transistor, in response to the feedback signal, controls a precharge current for precharging the bitline. The speed of the precharge operation may be increased and/or mismatch of the bias signals in precharging a plurality of bitlines may be reduced.
Abstract:
A nonvolatile memory system is operated by performing a program loop on each of a plurality of memory cells, each program loop comprising at least one program-verify operation and selectively pre-charging bit lines associated with each of the plurality of memory cells during the at least one program-verify operation.
Abstract:
A flash memory device controls a common source line voltage and performs a program verify method. A plurality of memory cells is connected between a bit line and the common source line. A data input/output circuit is connected to the bit line and is configured to store data to be programmed in a selected memory cell of the plurality of memory cells. The data input/output circuit maintains data to be programmed within the data input/output circuit during a program verify operation, and decreases noise in the common source line by selectively precharging the bit line based on the data to be programmed.