An absolute value circuit capable of providing, through an output terminal, a signal corresponding to the absolute value of the difference between a first input signal and a second input signal, comprises a first circuit, a second circuit and a uni-directional circuit.The first circuit is adapted for subtracting a current corresponding to said second input signal from a current corresponding to said first input signal and for supplying to said output terminal a current of one direction corresponding to the result of said subtraction in case said result is positive, or a current of the other direction corresponding to the result of said subtraction in case said result is negative.The second circuit is adapted for subtracting a current corresponding to said first input signal from a current corresponding to said second input signal and for supplying to said output terminal a current of one direction corresponding to the result of said subtraction in case said result is positive, or a current of the other direction corresponding to the result of said subtraction in case said result is negative.The uni-directional circuit is adapted for transmitting either one of said current of said one direction and said current of said the other direction supplied from said first and second circuit.