摘要:
Logic LSI includes first power domains PD1 to PD4, thick-film power switches SW1 to SW4, and power switch controllers PSWC1 to PSWC4. The thick-film power switches are formed by thick-film power transistors manufactured in a process common to external input/output circuits I/O. The first power domains include second power domains SPD11 to SPD42 including logic blocks, control circuit blocks SCB1 to SCB4, and thin-film power switches SWN11 to SWN42 that are connected to the thick-film power switches via virtual ground lines VSSM1 to VSSM4, and formed by thin-film power transistors manufactured in a process common to the logic blocks. In this way, power switches having different thickness of gate insulating films from one another are vertically stacked so as to be in a hierarchical structure, and each power switch is individually controlled by a power switch controller and a control circuit block correspondingly to each mode.
摘要:
In a low power consumption mode in which prior data is retained upon power shutdown, the return speed thereof is increased. While use of an existent data retaining flip-flop may be considered, this is not preferred since it increases area overhead such as enlargement of the size of a cell. A power line for data retention for power shutdown is formed with wirings finer than a usual main power line. Preferably, power lines for a data retention circuit are considered as signal lines and wired by automatic placing and mounting. For this purpose, terminals for the power line for data retention are previously designed by providing the terminals therefor for the cell in the same manner as in the existent signal lines. Additional layout for power lines is no longer necessary for the cell, which enables a decrease in the area and design by an existent placing and routing tool.
摘要:
The present invention provides a sense circuit for DRAM memory cell to cover the events that a sense time becomes remarkably longer when a power source voltage is lowered, a sense time under the low voltage condition becomes shorter when temperature rises and a sense time changes to a large extent for fluctuation of processes. The present invention provides the following typical effects. A switch means is provided between the bit line BL and local bit line LBL connected to the memory cells for isolation and coupling of these bit lines. The bit line BL is precharged to the voltage of VDL/2, while the local bit line LBL is precharged to the voltage of VDL. The VDL is the maximum amplitude voltage of the bit line BL. A sense amplifier SA comprises a first circuit including a differential MOS pair having the gate connected to the bit line BL and a second circuit connected to the local bit line LBL for full amplitude amplification and for holding the data. When the bit line BL and local bit line LBL are capacitance-coupled via a capacitor, it is recommended to use a latch type sense amplifier SA connected to the local bit line LBL.
摘要:
A semiconductor device includes a differential level converter circuit that receives a first signal and outputs a second signal of greater amplitude. The differential level converter has a first MISFET pair for receiving the first signal, a second MISFET pair for enhancing the withstand voltage of the first MISFET pair, and a third MISFET pair with cross-coupled gates for latching the second signal from output. The film thickness of the gate insulating films of the second and third MISFET pairs is made thicker than that of the first MISFET pair, and the threshold voltages of the first and second MISFET pairs are made smaller than that of the third MISFET pair. This level converter circuit operates at high speed even if there is a large difference in the signal amplitude before and after level conversion.
摘要:
A semiconductor integrated circuit device provided with a first circuit block BLK1, a second circuit block DRV1 and a conversion circuit MIO1 for connecting the first circuit block to the second circuit block. The first circuit block includes a first mode for applying a supply voltage and a second mode for shutting off the supply voltage. The conversion circuit is provided with a function for maintaining the potential of an input node of the second circuit block at an operation potential, thereby suppressing a penetrating current flow when the first circuit block is in the second mode. The conversion circuit (MIO1 to MIO4) are commonly used for connecting circuit blocks.
摘要:
A dynamic memory requires refreshing to retain data in its memory cells. This may cause access to the dynamic memory for purposes other than refreshing (external access) and access to it for refreshing to compete with each other, resulting in a performance deterioration. According to this invention, a pipelined dynamic memory (PDRAM) is used, and the pipeline frequency (CLK) of the pipelined dynamic memory is made higher than the frequency (CLK1) of external access, and access required for refreshing is made to an unoccupied slot (a timing when any external access request is never issued) in the pipeline of the pipelined dynamic memory. This makes refreshing of the internal dynamic memory an internal operation, which eliminates the need to take refreshing into consideration at the time external access is made, leading to improvement in operating ease and speed.
摘要:
A semiconductor integrated circuit device having a control signal system for avoiding failure to check an indefinite signal propagation prevention circuit, for facilitating a check included in an automated tool, and for facilitating a power shutdown control inside a chip. In the semiconductor integrated circuit device, power shutdown priorities are provided by independent power domains (Area A to Area I). A method for preventing a power domain having a lower priority from being turned OFF when a circuit having a high priority is turned ON is also provided.
摘要:
In a configuration provided with, for example, sixty four pieces of processor cores, an on-chip-memory, a bus commonly connected thereto, and others, the processor cores are operated by a power supply with low voltage and a clock with low frequency, and the bus is operated by a power supply with high voltage and a clock with high frequency. Each of the processor cores is provided with a bus interface and a frequency divider in order to absorb a power supply voltage difference and a frequency difference between the bus and each of them. The frequency divider generates the clock with low frequency from the clock with high frequency, and the bus interface is provided with a level shifting function, a data width converting function, a hand shaking function between the bus and the bus interface, and the like.
摘要:
A body bias control system allows for independent design of a functional module, thereby reducing the burden of designing the module. The body bias control system provides a switch circuit having an area in which the body bias is controlled independently of its outside portion, for controlling the supply of body bias in the vicinity of the area. Preferably three types of switches are provided for switching the body bias to suitable levels for a standby mode, a mode of normal operation and a mode of high-speed operation.
摘要:
The present invention provides a sense circuit for DRAM memory cell to cover the events that a sense time becomes remarkably longer when a power source voltage is lowered, a sense time under the low voltage condition becomes shorter when temperature rises and a sense time changes to a large extent for fluctuation of processes. The present invention provides the following typical effects. A switch means is provided between the bit line BL and local bit line LBL connected to the memory cells for isolation and coupling of these bit lines. The bit line BL is precharged to the voltage of VDL/2, while the local bit line LBL is precharged to the voltage of VDL. The VDL is the maximum amplitude voltage of the bit line BL. A sense amplifier SA comprises a first circuit including a differential MOS pair having the gate connected to the bit line BL and a second circuit connected to the local bit line LBL for full amplitude amplification and for holding the data. When the bit line BL and local bit line LBL are capacitance-coupled via a capacitor, it is recommended to use a latch type sense amplifier SA connected to bit line LBL.