US 6,204,707 B1 · Flip-flop circuit with clock signal control function and clock control circuit

Abstract

A flip-flop circuit 10 is provided with a discord detecting circuit DDC and a clock control circuit CCC. The discord detecting circuit DDC detects the discord of a data input signal DIS of the flip-flop circuit 10 with a data output signal DOS thereof. When the data input signal DIS discords with the data output signal DOS, the clock control circuit CCC supplies a short pulse to the flip-flop circuit 10 as an internal clock signal ICLK in synchronism with the rising of an external clock signal ECLK. On the other hand, when the data input signal DIS coincides with the data output signal DOS, the clock control circuit CCC supplies a low level signal to the flip-flop circuit 10 as the internal clock signal ICLK. Thus, it is possible to suppress electric power consumption required to supply a clock signal, and to prevent errors from being caused in a flip-flop operation.

Claims19

Dependent claims

A flip-flop circuit with clock signal control function comprises:

a data holding output circuit for receiving a data input signal and an internal clock signal and for holding a value of said data input signal in synchronism with said internal clock signal to output said value of said data input signal as a data output signal;
a discord detecting circuit for receiving said data input signal and data output signal of said data holding output circuit and for detecting the discord of said data input signal with said data output signal to output a discord signal;
and
a clock control circuit for receiving an external clock signal and said discord signal, and for outputting a shorter pulse than one cycle of said external clock signal as said internal clock signal in synchronism with the rising or falling of said external clock signal when said data input signal discords with said data output signal, and a signal of a first level as said internal clock signal when said data input signal coincides with said data output signal.

1 more element

Dependencies are inferred from the claim text.

Flip-flop circuit with clock signal control function and clock control circuit

Life of this patent

Flip-flop circuit with clock signal control function and clock control circuit

Life of this patent

Abstract

Claims19