Pipeline-based circuit with a postponed clock-gating mechanism for reducing power consumption and related driving method thereof

Abstract

A pipeline-based circuit with a postponed clock-gating mechanism and related driving method are disclosed for reducing power consumption, and the driving method does not deteriorate processing performance of the pipeline-based circuit. A pipeline-based circuit has a plurality of logic operators cascaded to form at least a pipeline, a pipeline control unit for generating at least a control signal to each logic operator for controlling whether one logic operator needs to pipe data to next logic operator, and a control value calculator for setting a valid bit of each logic operator following a currently activated logic operator according to the control signals generated from the pipeline control unit. When each logic operator begins operating, the related control value is used to determine whether or not a clock signal piping data of the present logic operator to next logic operator is gated to reduce power consumption. This postponed clock-gating mechanism avoids the degradation of pipeline clock speed limitation.

Description

BACKGROUND OF INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a pipeline-based circuit. In particular, the present invention discloses a pipeline-based circuit utilizing a postponed clock-gating mechanism for reducing power consumption. [0003] 2. Description of the Prior Art [0004] An accurate clock signal is a key factor for a logic circuit to perform a correct logic operation. That is, the clock signal is used to drive kernel circuit units such as counters and registers within the logic circuit, and a stable clock signal such as a clock signal generated from a crystal oscillator always functions as a reference clock to arbitrate operations of the circuit units within the logic circuit. However, all of the circuit units within the logic circuit are not always active. When some of the circuit units enter an idle mode, these idle circuit units do not need to be driven by the clock signal continuously for performing related operations. If the clock s...

AI Technical Summary

Benefits of technology

[0016] It is an advantage of the present invention that the claimed pipeline-based circuit can prevent the possibly late-arrived control signal from affecting the operation of the clock-gating unit. That is, the claimed pipeline-based circuit is capable of gating clock signals in time for saving power successfully. In addition, the claimed pipeline-based circuit needs to implement additional second buffer units only. The circuit structure of the second buffer unit is simple, and the implementation is straightforward. Therefore, the control values can be easily applied to pipeline-based circuits having different pipeline structures for accomplishing the same purpose of reducing power consumption. In addition, the postponed clock-gating mechanism avoids the degradation of pipeline clock speed.

[0017] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in the various figures and drawings.

Problems solved by technology

However, all of the circuit units within the logic circuit are not always active.

If the clock signal is still inputted into the idle circuit units, power consumption of the logic circuit is increased unnecessarily.

It is well known that the power consumption of the logic circuit is mainly generated from delivering the clock signal to these circuit units and enabling these circuit units to run related logic operations.

Furthermore, a glitch is induced to affect the operation of the processing unit 32b.

The unwanted glitch induced for each of the clock signals CLK_GA, CLK_GB, CLK_GC likely results in the pipeline-based logic circuit 30 functioning incorrectly.

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