Abstract: A manner of generating internal voltages such as a high voltage, an intermediate voltage and an internal power supply voltage is switched in accordance with a power supply level setting signal. When the voltage level of an external power supply voltage is low, a current drive transistor receiving an output of a comparing circuit and an auxiliary drive transistor are forcedly set in a conductive state, and external power supply voltage is transmitted on an internal power supply line. At this time, the comparing operation of the comparing circuit is stopped. When the level of the external power supply voltage is high, the comparing circuit is activated down convert the external power supply voltage for generating a peripheral power supply voltage on the internal power supply line.

Abstract: A substrate treating apparatus disclosed herein realizes improved throughput. The substrate treating apparatus according to this invention includes an antireflection film forming block, a resist film forming block and a developing block arranged in juxtaposition. Each block includes chemical treating modules, heat-treating modules and a single main transport mechanism. The main transport mechanism transports substrates within each block. Transfer of the substrates between adjacent blocks is carried out through substrate rests. The main transport mechanism of each block is not affected by movement of the main transport mechanisms of the adjoining blocks. Consequently, the substrates may be transported efficiently to improve the throughput of the substrate treating apparatus.

Abstract: Data pad regions are arranged in four divided regions of a semiconductor memory chip of a rectangular shape, respectively, and data pads are selectively utilized in each of the four divided regions in accordance with a word structure. Thus, it is possible to implement a semiconductor memory chip capable of being assembled in both a single chip package and a multi chip package.

Abstract: The semiconductor memory device includes a refresh timer for determining a refresh cycle of self-refresh operation. The refresh timer includes a voltage regulator, a ring oscillator and a counter. The voltage regulator generates a bias voltage having positive temperature characteristics. The ring oscillator varies an oscillation cycle of a pulse signal according to the bias voltage. The counter counts a prescribed number of pulse signals and generates a refresh signal for executing refresh operation. The semiconductor memory device thus varies the refresh cycle according to a temperature change, and executes refresh operation with an appropriate refresh cycle.

Abstract: An input circuit includes a gate circuit receiving an output power supply voltage that determines the logic level of an input signal or a comparison circuit receiving an input signal and a reference voltage depending on the output power supply voltage supplied from a pad different from a power supply pad for an output circuit.

Abstract: A row address decoder of a semiconductor memory device generates internal row address signals RAD<0:11> and /RAD<0:11> by switching most significant bit and least significant bit of row address signals RA<0:11> and /RA<0:11> that correspond to address signals A0 to A11, respectively. In a twin cell mode, the least significant bits RAD<0> and /RAD<0> of the internal row address signals corresponding to the most significant bits RA<11> and /RA<11> of the row address signal that are not used are selected simultaneously by row address decoder, and two adjacent word lines are activated simultaneously. Consequently, the configuration of memory cell in the semiconductor memory device can electrically be switched from the normal single memory cell type to the twin memory cell type.

Abstract: A refresh array activating signal is activated in accordance with a refresh request and specific address bit(s) of a refresh address. Specific lower bit(s) of a refresh address counter is (are) utilized as the specific address bit(s) of the refresh address, and the specific address bit(s) is (are) utilized as upper bit(s) of the refresh address. Thus, in the self-refresh mode, refresh can be performed for a prescribed address region at uniform intervals, with a lengthened refresh interval, consuming less current. A semiconductor memory device is provided which allows current consumption to be distributed on a time basis and to be reduce in a self-refresh mode is provided.

Abstract: In the output circuit, at a subsequent stage of a gate circuit operating with a power supply voltage related to a first power supply voltage, a latch circuit formed of an inverter circuit and a MOS transistor is arranged, and is supplied with a second power supply voltage as an operating power supply voltage. An output buffer circuit is driven in accordance with an output signal of the latch circuit. When the first power supply voltage is powered down, the latch circuit receiving and operating with the second power supply voltage holds a signal voltage to be attained in a standby state and thus the output buffer circuit is reliably held in an output high impedance state. In a semiconductor device of a double power supply configuration, even when one power supply is powered down, the output buffer circuit can reliably be set to an output high impedance state.

Abstract: A bias voltage having a positive temperature dependency is supplied to a current source that determines the operating current of a refresh timer that issues a refresh request to allow the driving current of the current source to have a positive temperature characteristic. In this manner, the refresh cycle of the refresh timer shortens the issue intervals when the temperature rises, and lengthens the issue intervals of the refresh request when the temperature decreases. Thus, the consumed current for the refresh at room temperature is reduced. Consequently, the consumed current in a self-refresh mode under the room temperature condition can be reduced.

Abstract: A semiconductor memory device includes banks, predecoders, a latch circuit, a counter, a fuse and buffers. The bank includes a plurality of memory cells arranged in rows and columns, and others. The predecoders are disposed in a central portion of the semiconductor memory device. The predecoder produces a predecode signal for selecting each of the banks based on a bank address received from the buffer, and outputs the predecode signal to the banks. The predecoder produces the predecode signal for selecting each of the banks based on the bank address, and outputs the predecode signal to the banks. Consequently, interconnections in the central portion can be reduced in number.

Abstract: A clock buffer of a DRAM includes: a first NAND gate which is driven by a first internal power supply voltage (2.5 V) and which determines the level of an input clock signal if the DRAM is used for a TTL-system interface (MLV=2.5 V); and a second NAND gate which is driven by a second internal power supply voltage (1.8 V) and which determines the level of the input clock signal if the DRAM is used for a 1.8 V-system interface (MLV=0 V). Accordingly, in each of the first and second NAND gates, sizes of four MOS transistors can be set at optimum values, respectively.

Abstract: Data specifying details of refresh to be executed in the self-refresh mode is stored in a register circuit in a mode register. A refresh period and refresh region are determined according to data stored in register circuit and a refresh control circuit generates a control signal and a refresh address that are required for refresh. Stored data can be stably held in the self-refresh mode in which data holding is performed with reduced current consumption.

Abstract: A level conversion circuit is provided, at an output, with an initialization circuit for setting the output signal of the level conversion circuit for generating a power cut enable signal controlling a deep power down mode to a predetermined inactive state upon power up. The initialization circuit is constituted by, for example, a capacitive element connected to the output node of the level conversion circuit to pull up the voltage of the output node upon power up, and a latch circuit latching the voltage level of the output node. When power is on, the power cut enable signal is forcibly inactivated by the initialization circuit to generate a periphery power supply voltage. The internal node of the level conversion circuit is initialized according to the output signal of a control circuit receiving the periphery power supply voltage as an operating power supply voltage.

Abstract: Data for switching a slew rate of a data output circuit included in a data input/output circuit between a slew rate in a normal mode and a slow slew rate is stored in a mode register. According to the data stored in mode register, a slew rate setting signal is generated. According to a slew rate switching circuit, the slew rate of the data input/output circuit is switched between a slew rate in the normal mode and a slow slew rate slower than the slew rate in the normal mode. A data output circuit is achieved which occupies a small area, is capable of setting a slew rate slower than the slew rate in a normal mode and outputting data without causing an erroneous operation with a low consumption current even when the slew rate is adjusted.

Abstract: In a control circuit and an address buffer circuit, buffer circuits of plural types are provided to each of pin terminals and an input buffer of one type is activated according a state control signal group. In a standby state, current paths of the control buffer circuit and the address buffer circuit are selectively cut off according to a CS cut mode instructing signal stored in a mode register and an internal chip select signal. Furthermore, when a low power consumption mode is specified, a current path of a CLK buffer for generating an internal clock signal is cut off according to an external clock enable signal and a low power mode instructing signal, and the current paths of the control buffer circuit and the address buffer circuit are also cut-off.

Abstract: The semiconductor memory device includes a refresh timer for determining a refresh cycle of self-refresh operation. The refresh timer includes a voltage regulator, a ring oscillator and a counter. The voltage regulator generates a bias voltage having positive temperature characteristics. The ring oscillator varies an oscillation cycle of a pulse signal according to the bias voltage. The counter counts a prescribed number of pulse signals and generates a refresh signal for executing refresh operation. The semiconductor memory device thus varies the refresh cycle according to a temperature change, and executes refresh operation with an appropriate refresh cycle.

Abstract: A clock buffer of a DRAM includes: a first NAND gate which is driven by a first internal power supply voltage (2.5 V) and which determines the level of an input clock signal if the DRAM is used for a TTL-system interface (MLV=2.5 V); and a second NAND gate which is driven by a second internal power supply voltage (1.8 V) and which determines the level of the input clock signal if the DRAM is used for a 1.8 V-system interface (MLV=0 V). Accordingly, in each of the first and second NAND gates, sizes of four MOS transistors can be set at optimum values, respectively.

Abstract: Data pad regions are arranged in four divided regions of a semiconductor memory chip of a rectangular shape, respectively, and data pads are selectively utilized in each of the four divided regions in accordance with a word structure. Thus, it is possible to implement a semiconductor memory chip capable of being assembled in both a single chip package and a multi chip package.

Abstract: A row address decoder of a semiconductor memory device generates internal row address signals RAD<0:11>and /RAD<0:11>by switching most significant bit and least significant bit of row address signals RA<0:11>and /RA<0:11>that correspond to address signals A0 to A11, respectively. In a twin cell mode, the least significant bits RAD<0>and /RAD<0>of the internal row address signals corresponding to the most significant bits RA<11>and /RA<11>of the row address signal that are not used are selected simultaneously by row address decoder, and two adjacent wold lines are activated simultaneously. Consequently, the configuration of memory cell in the semiconductor memory device can electrically be switched from the normal single memory cell type to the twin memory cell type.

Abstract: A manner of generating internal voltages such as a high voltage, an intermediate voltage and an internal power supply voltage is switched in accordance with a power supply level setting signal. When the voltage level of an external power supply voltage is low, a current drive transistor receiving an output of a comparing circuit and an auxiliary drive transistor are forcedly set in a conductive state, and external power supply voltage is transmitted on an internal power supply line. At this time, the comparing operation of the comparing circuit is stopped. When the level of the external power supply voltage is high, the comparing circuit is activated down convert the external power supply voltage for generating a peripheral power supply voltage on the internal power supply line.