Abstract:
PURPOSE: A composite FFT(Fast Fast Transform) calculating device, a composite FFT calculating method, and a recording medium adapted thereto are provided to minimize an FFT calculation speed. CONSTITUTION: Input registers(202,204) load data to be used for a calculation from read buses. Coefficient registers(206,208) load a sine value and a cosine value to be used for a calculation from the read buses. An adder(214) and a subtracter(216) add or subtract values stored in the Input registers(202,204). Multipliers(218,220) multiply an output of the subtracter(216) by outputs of the coefficient registers(206,208). Four storage registers(224,226,228,230) executes a complex calculation. Multiplexers(210,212) support operations of the adder(214) and the subtracter(216). A multiplexer(232) controls an output. A controller(234) controls operations of the above elements.
Abstract:
PURPOSE: A semiconductor memory device having a block write function and a block write method are provided to prevent a data interference effect between activated columns by providing a load current to a pair of masked input/output line from an additional load current source during a block write cycle, and to perform the block write function without increasing an area of a memory core. CONSTITUTION: Input/output line pair(IO0,IOB0) is in a write masking state, and input/output line pair(IO7,IOB7) is in a block write state. Corresponding bit line pairs((BL0,BLB0),(BL1,BLB1),(BL7,BLB7)) are connected to the input/output line pair(IO0,IOB0) through column selectors(CS0-CS7). The column selectors comprises two NMOS transistors. In one NMOS transistor, a drain is connected to a bit line(BLi) and a source is connected to an input/output line(IOi) and a gate is connected to a column selection line(CSLi). In another NMOS transistor, a drain is connected to a bit line(BLBi) and a source is connected to an input/output line(IOBi) and a gate is connected to a column selection line(CSLi). The column selector is enabled one by one in a normal write cycle but in a block write mode eight column selectors are enabled simultaneously. Bit line sense amplifiers(SAMP0-SAMP7) to amplify data of a memory cell enabled by a word line are connected to each bit line pair. The bit line sense amplifier includes an NMOS amplifier(NSA) and a PMOS amplifier(PSA) arranged adjacent to the column selector. 256 memory cells are connected to each bit line pair to form a memory column. And, the first load current source(WLCSi) and the second load current source(RLCSi) and a write driver(WDi) are connected to each input/output line pair.
Abstract:
PURPOSE: A DRAM SRAM compound semiconductor device is provided which transfers data effectively between a DRAM and a SRAM embodied on one chip. CONSTITUTION: The device includes a DRAM(100) as a main memory, and includes a SRAM(200) as a cache memory. A read operation of the DRAM and a write operation of the SRAM are controlled by a DRAM read control signal simultaneously, And a write operation of the DRAM and a read operation of the SRAM are controlled by a DRAM write control signal simultaneously. According to the DRAM and SRAM compound semiconductor device, a DRAM write command and a DRAM read command is given continuously. Therefore, the data exchange speed of the DRAM and the SRAM are improved steeply. And, after the read operation of the DRAM is completed, the write operation of the SRAM starts, and also because after the read operation of the SRAM is completed the write operation of the DRAM starts, there is no current consumption due to void data. Also, it is easy to control the SRAM because the SRAM is controlled by the command of the DRAM.