摘要:
A system and method for accessing a data cache having at least two ways for storing data at the same addresses. A first and second tag memory store first and second sets of tags identifying data stored in each of the ways. A translation device determines from a system address a tag identifying one of the ways. A first comparator compares tags in the address with a tag stored in the first tag memory. A second comparator compares a tag in the address with a tag stored in the second tag memory. A clock signal supplies clock signals to one or both of the ways in response to an access mode signal. The system can be operated so that either both ways of the associative data cache are clocked, in a high speed access mode, or it can apply clock signals to only one of the ways selected by an output from the first and second comparators in a power efficient mode of operation.
摘要:
The present invention provides a system and method for providing a standard cell library for reduced leakage and improved performance. The standard cell library comprises at least two sets of threshold voltage cells. At least one of the sets includes non-mixed threshold voltage cells. At least one of the sets includes mixed threshold voltage cells. The mixed threshold voltage cells have at least one threshold voltage cell having a first threshold voltage and a second threshold voltage cell having a second threshold voltage. The first and second threshold voltages are different. The mixed threshold voltage cells have substantially the same footprint as the non-mixed threshold voltage cell.
摘要:
An interconnect structure, comprising: a lower level wire having a side and a bottom, the lower level wire comprising: a lower core conductor and a lower conductive liner, the lower conductive liner on the side and the bottom of the lower level wire; an upper level wire having a side and a bottom, the upper level wire comprising an upper core conductor and an upper conductive liner, the upper conductive liner on the side and the bottom of the upper level wire; and the upper conductive liner in contact with the lower core conductor and also in contact with the lower conductive liner in a liner-to-liner contact region.
摘要:
A level converter for interfacing two circuits supplied by different supply voltages, and integrated circuit including the level converter interfacing circuit in two different voltage islands. A first buffer is supplied by a virtual supply and receives an input signal from a lower voltage circuit. The first buffer drives a second buffer, which is supplied by a higher supply voltage. An output from the second buffer switches a supply select to selectively pass the higher supply voltage or a reduced supply voltage to the first buffer.
摘要:
A voltage island is disclosed. The voltage island comprises a physical domain and a lower voltage supply rail within the physical domain. The voltage island also includes an upper voltage supply rail within the physical domain. The physical domain is coupled to the appropriate voltage supply rail to ensure reverse biased junctions. Accordingly, a system in accordance with the present invention allows circuit placements associated with multiple voltage islands within a common circuit row or even adjacent circuit rows to be utilized in which the area effectiveness is greatly improved. The use of common Nwell biasing connected to the higher power supply ensures no forward biased junctions and allows butted circuit placement in cases where the other circuit physical constraints permit. This configuration will minimize the density loss associated multiple voltage island implementations.
摘要:
A method and a flip-flop is disclosed in which power consumption is reduced in a standby mode. In a first aspect, the flip-flop comprises a first latch adapted to be coupled to a first power supply and a second latch coupled to the first latch and adapted to be coupled to a second power supply. The first and second power supplies are independently controllable to minimize power consumption in a standby mode. In a second aspect, a method for minimizing the power consumption of a flip-flop is also disclosed. The flip-flop includes a first latch and a second latch coupled thereto. The method comprises providing a first independently controllable power supply coupled to the master latch; and providing a second independently controllable power supply coupled to the slave latch. The method further includes reducing the voltage of at least one of the first and second power supplies responsive to the detection of a power saving mode.
摘要:
A memory bit line multiplexor circuit is disclosed. The circuit comprises at least one memory cell arrangement. The circuit includes a first active device coupled to the at least one memory cell arrangement and for coupling a first node to a second node within the circuit. The first active device is controlled by a write through read (!wtr) signal. The circuit includes a second active device coupled to the second node and a gate. The gate has a first input coupled to the first node; a second input coupled to the !WTR signal, and a third input being controlled by an inversion of the output of the circuit. The gate and the second active device provide a pulsed self-timed response that minimizes power consumption while optimizing performance of the circuit. A circuit in accordance with the present invention is disclosed in which the most power, and area efficient realizations can be employed for applications requiring broad power supply operating ranges. The circuit employs a simple logic gate system configured to create a self-timed pulsed stimulus for allowing improved performance over a very broad Vdd operation range while simultaneously reducing power.
摘要:
The protection circuit of the present invention addresses the problem of indeterminate logic levels caused by loss of one of the power supplies in a two-power-supply CMOS integrated circuit. The circuit of the present invention replaces the typical scheme of power supply sequencing to fix the problem. The circuit disclosed herein detects the state of the core voltage and disables the output drivers when the core voltage is detected as being off. The disabled drivers are put into a high impedance state, thereby eliminating the potential for damage and eliminating the need for power supply sequencing. The invention also protects against the sudden loss of the integrated circuit core voltage, VDD, power supply during normal operation.
摘要:
A system and method for accurately measuring the duty cycle of an input periodic pulsed signal. The system includes a device for converting the input signal to be measured into a first dc voltage and, a device maintaining representations of potential duty cycle values that are selectable in an iterative fashion. At each iteration, in response to a selected duty cycle value, a second dc voltage is generated that represents the difference between the duty cycle of the input signal to be measured and the duty cycle represented by a current selected encoded duty cycle value. A selection mechanism responds to the first and second dc voltages for selecting a different encoded duty cycle for a successive iteration. The system selects an encoded duty cycle value at each iteration until the first and second dc voltages match. At such time, the current selected encoded duty cycle value represents the duty cycle of the input voltage for output thereof. By representing the input signal's duty cycle as a dc voltage, the system may measure the input signal's duty cycle accurately regardless of its frequency.
摘要:
The protection circuit of the present invention addresses the problem of indeterminate logic levels caused by loss of one of the power supplies in a two-power-supply CMOS integrated circuit. The circuit of the present invention replaces the typical scheme of power supply sequencing to fix the problem. The circuit disclosed herein detects the state of the core voltage and disables the output drivers when the core voltage is detected as being off. The disabled drivers are put into a high impedance state, thereby eliminating the potential for damage and eliminating the need for power supply sequencing. The invention also protects against the sudden loss of the integrated circuit core voltage, VDD, power supply during normal operation.