摘要:
In a driver circuit for driving a pair of data lines, the amplitude of a differential input signal is reduced from 2.5 V to 0.6 V, which is smaller than a conventional lower-limit source voltage (approximately 1.5 V). The amplitude of the differential signal transmitted through the pair of data lines is amplified to 2.5 V by an amplifying circuit and the resulting signal is then latched by a latch circuit. After the latching by the latch circuit, the operation of the amplifying circuit is halted. The driver circuit is constituted solely by a plurality of NMOS transistors so as not to increase a leakage current flowing in the off state. Here, the threshold voltage of the NMOS transistor positioned on the ground side is reduced to a conventional lower-limit value (0.3 V to 0.6 V), while the threshold voltage of the NMOS transistor on the power-source side to a value lower than the above lower-limit value (0 V to 0.3 V), thereby enhancing a driving force of the NMOS transistor on the power-source side.
摘要:
In a driver circuit for driving a pair of data lines, the amplitude of a differential input signal is reduced from 2.5 V to 0.6 V, which is smaller than a conventional lower-limit source voltage (approximately 1.5 V). The amplitude of the differential signal transmitted through the pair of data lines is amplified to 2.5 V by an amplifying circuit and the resulting signal is then latched by a latch circuit. After the latching by the latch circuit, the operation of the amplifying circuit is halted. The driver circuit is constituted solely by a plurality of NMOS transistors so as not to increase a leakage current flowing in the off state. Here, the threshold voltage of the NMOS transistor positioned on the ground side is reduced to a conventional lower-limit value (0.3 V to 0.6 V), while the threshold voltage of the NMOS transistor on the power-source side to a value lower than the above lower-limit value (0 V to 0.3 V), thereby enhancing a driving force of the NMOS transistor on the power-source side.
摘要:
In a driver circuit for driving a pair of data lines, the amplitude of a differential input signal is reduced from 2.5 V to 0.6 V, which is smaller than a conventional lower-limit source voltage (approximately 1.5 V). The amplitude of the differential signal transmitted through the pair of data lines is amplified to 2.5 V by an amplifying circuit and the resulting signal is then latched by a latch circuit. After the latching by the latch circuit, the operation of the amplifying circuit is halted. The driver circuit is constituted solely by a plurality of NMOS transistors so as not to increase a leakage current flowing in the off state. Here, the threshold voltage of the NMOS transistor positioned on the ground side is reduced to a conventional lower-limit value (0.3 V to 0.6 V), while the threshold voltage of the NMOS transistor on the power-source side to a value lower than the above lower-limit value (0 V to 0.3 V), thereby enhancing a driving force of the NMOS transistor on the power-source side.
摘要:
In a driver circuit for driving a pair of data lines, the amplitude of a differential input signal is reduced from 2.5 V to 0.6 V, which is smaller than a conventional lower-limit source voltage (approximately 1.5 V). The amplitude of the differential signal transmitted through the pair of data lines is amplified to 2.5 V by an amplifying circuit and the resulting signal is then latched by a latch circuit. After the latching by the latch circuit, the operation of the amplifying circuit is halted. The driver circuit is constituted solely by a plurality of NMOS transistors so as not to increase a leakage current flowing in the off state. Here, the threshold voltage of the NMOS transistor positioned on the ground side is reduced to a conventional lower-limit value (0.3 V to 0.6 V), while the threshold voltage of the NMOS transistor on the power-source side to a value lower than the above lower-limit value (0 V to 0.3 V), thereby enhancing a driving force of the NMOS transistor on the power-source side.
摘要:
In a driver circuit for driving a pair of data lines, the amplitude of a differential input signal is reduced from 2.5 V to 0.6 V, which is smaller than a conventional lower-limit source voltage (approximately 1.5 V). The amplitude of the differential signal transmitted through the pair of data lines is amplified to 2.5 V by an amplifying circuit and the resulting signal is then latched by a latch circuit. After the latching by the latch circuit, the operation of the amplifying circuit is halted. The driver circuit is constituted solely by a plurality of NMOS transistors so as not to increase a leakage current flowing in the off state. Here, the threshold voltage of the NMOS transistor positioned on the ground side is reduced to a conventional lower-limit value (0.3 V to 0.6 V), while the threshold voltage of the NMOS transistor on the power-source side to a value lower than the above lower-limit value (0 V to 0.3 V), thereby enhancing a driving force of the NMOS transistor on the power-source side.
摘要:
N-piece redundant address comparing circuits are individually composed of impedance converting circuits, so that information using redundancy is transmitted as an impedance value. Consequently, even though the N becomes larger as the capacity of a memory becomes larger, a signal line having large capacitance and the node of a redundant judging circuit are not charged or discharged. A high-speed operation can be realized without being affected by the capacitance of the signal line or by the capacitance of the node of the redundant judging circuit.
摘要:
In a synchronous DRAM required to be capable of performing high-speed consecutive operations in synchronism with a clock signal, a DBI-line pair is connected between a DQ-line pair and an RDB-line pair, and pipeline operation whose single cycle time is divided into four periods is employed. This S-DRAM has following: a first precharge circuit for precharging or voltage-equalizing the DQ-line pair to a power supply voltage level in the first and forth periods only; a second precharge circuit for voltage-equalizing the DBI-line pair to a ground voltage level in the first and second periods only; a third precharge circuit for voltage-equalizing the RDB-line pair to the power supply voltage level in the first and second periods only; first and second differential amplifiers for transmitting data on the DQ lines onto the DBI lines in the third period and for holding the data on the DBI lines in the fourth period; and a third differential amplifier which transmits the data on the DBI lines onto the RDB lines in the third period and which holds the data on the RDB lines in the fourth period.
摘要:
An external power supply voltage V.sub.CC is applied to a peripheral circuit as a first internal power supply voltage V.sub.PERI. A power supply voltage control circuit outputs a voltage control signal V.sub.SIG of a high logic level if V.sub.CC is not greater than a low limit voltage V.sub.0L in a voltage range specified by VCC recommended operating conditions, otherwise it outputs V.sub.SIG of a low logic level. A power supply circuit applies a second internal power supply voltage V.sub.W and a third internal power supply voltage V.sub.WORD to a memory cell section. V.sub.W is equal to V.sub.PERI if V.sub.SIG is HIGH, while on the other hand V.sub.W is a voltage as a result of boosting V.sub.PERI. V.sub.WORD is a voltage as a result of boosting VW to a further extent. A row decoder sends out V.sub.W onto an enable signal line of a row of sense amplifiers, and V.sub.WORD onto a word line of a memory cell array so that V.sub.W becomes a high-logic-level data write voltage to a memory cell. This adequately prolongs the data-holding time with no sacrifice in memory cell voltage resistance.
摘要:
In a synchronous DRAM, a redundancy judging circuit has a frequency dividing circuit and a plurality of judging circuits each having two address comparing circuits and one output circuit. When an internal CAS signal having an activating period of time according to a data burst length, is activated, the frequency dividing circuit divides the frequency of an internal continuous clock signal having the same time period of one cycle and the same phase as those of an external clock signal, and generates complementary clock signals each having a time period of one cycle twice the time period of one cycle of the internal continuous clock signal. A pair of address comparing circuits to which supplied is an internal column address to be successively updated according to the data burst length, alternately supply a redundancy judgement signal after alternately comparing the same defective column address previously programmed therein, with an internal column address according to the complementary clock signals supplied from the frequency dividing circuit. The output circuit supplies a redundancy judgement signal when either of the judgement signals is obtained. Thus, there is made an accurate column redundancy judgement at the time when the external clock signal is high in frequency.
摘要:
In a synchronous DRAM, a redundancy judging circuit has a frequency dividing circuit and a plurality of judging circuits each having two address comparing circuits and one output circuit. When an internal CAS signal having an activating period of time according to a data burst length, is activated, the frequency dividing circuit divides the frequency of an internal continuous clock signal having the same time period of one cycle and the same phase as those of an external clock signal, and generates complementary clock signals each having a time period of one cycle twice the time period of one cycle of the internal continuous clock signal. A pair of address comparing circuits to which supplied is an internal column address to be successively updated according to the data burst length, alternately supply a redundancy judgement signal after alternately comparing the same defective column address previously programmed therein, with an internal column address according to the complementary clock signals supplied from the frequency dividing circuit. The output circuit supplies a redundancy judgement signal when either of the judgement signals is obtained. Thus, there is made an accurate column redundancy judgement at the time when the external clock signal is high in frequency.