摘要:
An internal voltage generating circuit generates and supplies a boosted voltage higher than an internal power supply voltage, as an operating power supply voltage, to a sense amplifier in a read circuit for reading data of a memory cell. A bit line precharge current supplied via an internal data line is produced from the internal power supply voltage. It is possible to provide a nonvolatile semiconductor memory device, which can perform a precise sense operation and an accurate reading of data even under a low power supply voltage condition.
摘要:
A phase difference between a feedback clock signal corresponding to an internal clock signal generated via a variable delay line and a buffered clock signal corresponding to an external clock signal is detected by a phase detector, and a result of detection is transferred via a shifting circuit. When a down signal from the shifting circuit is activated by a delay control circuit, the down instruction signal is forcibly maintained to be active for a predetermined clock cycle period. When the down instruction signal becomes inactive from the active state, a count control circuit sets a count unit of the counting circuit to the minimum value. The delay amount of the variable delay line is set according to an output count bit of the counting circuit. Therefore, it is possible to reduce the number of clock cycles required until an internal clock signal is synchronized in phase with the external clock signal.
摘要:
A selector selects one standard voltage from among divided voltages from a voltage dividing circuit and a reference voltage from a reference voltage generating circuit, in accordance with a test mode enable signal and a reference voltage select signal. An internal voltage generating circuit receives the standard voltage from the selector and generates an internal power supply voltage.
摘要:
A semiconductor memory device includes a memory having a predetermined number of divided memory spaces, a register that stores data indicating whether a refresh operation is required or not with respect to each memory space, a row address counter that, with reference to the register, counts up an address while skipping an address requiring no refresh operation, to thereby generate an address of the memory space to be refreshed, and a refresh cycle generating circuit that with reference to the register 15, generates a refresh cycle with a cycle which varies according to the number of the memory space requiring the refresh operation.
摘要:
An internal voltage generating circuit generates and supplies a boosted voltage higher than an internal power supply voltage, as an operating power supply voltage, to a sense amplifier in a read circuit for reading data of a memory cell. A bit line precharge current supplied via an internal data line is produced from the internal power supply voltage. It is possible to provide a nonvolatile semiconductor memory device, which can perform a precise sense operation and an accurate reading of data even under a low power supply voltage condition.
摘要:
An internal voltage generating circuit generates and supplies a boosted voltage higher than an internal power supply voltage, as an operating power supply voltage, to a sense amplifier in a read circuit for reading data of a memory cell. A bit line precharge current supplied via an internal data line is produced from the internal power supply voltage. It is possible to provide a nonvolatile semiconductor memory device, which can perform a precise sense operation and an accurate reading of data even under a low power supply voltage condition.
摘要:
An internal voltage generating circuit generates and supplies a boosted voltage higher than an internal power supply voltage, as an operating power supply voltage, to a sense amplifier in a read circuit for reading data of a memory cell. A bit line precharge current supplied via an internal data line is produced from the internal power supply voltage. It is possible to provide a nonvolatile semiconductor memory device, which can perform a precise sense operation and an accurate reading of data even under a low power supply voltage condition.
摘要:
Two delay lines included in a DLL circuit receive clock signals complementary to each other to output complementary clock signals CLKP and CLKN for data output. A power supply generation circuit applying a power supply to the two delay lines is arranged at an equivalent position from the two delay line. An equal potential is supplied to the two delay lines by, for example, setting lengths of two power supply lines from a branch point equal to each other. By doing so, delay time of one delay line can be set equal to delay time of the other delay line and a phase error between clock signals CLKP and CLKN can be reduced. Therefore, a semiconductor device on which the DLL circuit having the improved phase error is mounted can be provided.
摘要:
In a DLL circuit of a DDR SDRAM, in addition to a replica buffer for compensating delay in an output buffer, a replica buffer for compensating flight time is provided. The phase of a clock signal CLKP outputted to the outside so as to be locked with a clock signal BUFFCLK can be adjusted in accordance with a control signal b[1:0]. For a controller receiving data in a lump from a plurality of semiconductor memory devices, the arriving timings of data from the semiconductor memory devices can be aligned. Therefore, it is unnecessary to capture data in response to a data strobe signal DQS, so that burden on the controller is lessened.