Maximum signal determining circuit

Claim 2

In a system including a plurality of conductors each carrying a respective signal, a circuit for providing an indication of which conductor is presently carrying that signal whose amplitude is the highest of all the signals, said circuit comprising, in combination: a. a plurality of amplifiers, one for each conductor, each having an input connected to a respective conductor; b. maximum signal value receiving means connected to the outputs of all of said amplifiers and having a common output at which appears a signal corresponding to the highest of the output signals of all of said amplifiers; c. feedback means connected between said common output and each said amplifier for applying to each said amplifier an inverted input whose amplitude is a predetermined fraction of the common output signal; and d. a plurality of second feedback means, each including a switch element and each connected between the output and the input of a respective amplifier, each said switch element being operative for feeding a predetermined fraction of its amplifier output back to its input only when the output from its respective amplifier is less than the highest of all the amplifier outputs so as to cause the output from each such amplifier to produce an output signal which is approximately equal to the difference between its associated input signal and the highest one of all the signals carried by said conductors.

Claim 3

An arrangement as defined in claim 1 wherein said maximum signal value receiving means comprise a plurality of diodes, one for each said amplifier, each connected between the output of a respective amplifier and said common output and poled to have a forward conduction direction from its respective amplifier output to said common output, each said switch element is constituted by a second diode having one end connected to the output of its respective amplifier and poled to have a forward conduction direction toward said amplifier output, and each said second feedback means further includes voltage divider means connected between said common output and the other end of its respective second diode, whereby the output signal from each amplifier appears at said other end of said second diode.

Claim 4

An arrangement as defined in claim 2 further comprising a plurality of threshold value circuits, one for each said amplifier, each having an information input connected to said other end of the second diode associated with its respective amplifier and a threshold value input for receiving a signal which determines the level which its information input signal must have in order for said threshold value circuit to produce an output signal, and threshold value means connected to the threshold inputs of all of said threshold value circuits for applying the same threshold value signal to all of said threshold inputs.

Claim 5

An arrangement as defined in claim 3 further comprising a doublecheck circuit having a plurality of inputs each connected to the output of a respective one of said threshold value circuits and an output which pRoduces a signal whenever more than one of said threshold value circuits emits an output signal.

Claim 6

An arrangement as defined in claim 4 further comprising an additional threshold value circuit having an information input connected to said common output and a threshold value input for providing a threshold value signal which determines the level which the signal at its information input must have in order for said additional threshold value circuit to emit an output signal.

Claim 7

An arrangement as defined in claim 5 further comprising reject means connected to the output of said doublecheck circuit and the output of said additional threshold value circuit for emitting a reject signal whenever said doublecheck circuit emits a signal or said additional threshold value circuit does not emit a signal.

Claim 8

An arrangement as defined in claim 2 wherein said feedback means includes a plurality of first impedance elements, one for each said amplifier, each connected between said common output and its respective amplifier, and said voltage divider means associated with each said amplifier includes a second impedance element having the same impedance as said first impedance element and connected between said other end of said second diode of its associated second feedback means and said amplifier input, and a third impedance element associated with each said amplifier and connected between said amplifier input and ground to form a voltage divider with each of said first and second impedance elements associated with the same amplifier.

Claim 9

An arrangement as defined in claim 1 further comprising an additional threshold value circuit having an information input connected to said common output and a threshold value input for providing a threshold signal whose value determines the level which said information signal must have in order to cause said additional threshold value circuit to produce an output.

Claim 10

An arrangement as defined in claim 1 in combination with a character-reading device for identifying each character read.

Claim 11

In a system including a plurality of conductors each carrying a respective signal, a circuit for providing an indication of which conductor is presently carrying that signal whose amplitude is the highest of all the signals, said circuit comprising in combination: a. a plurality of amplifiers, one for each conductor, each having an input connected to a respective conductor; b. maximum signal value receiving means connected to the outputs of all of said amplifiers and having a common output at which appears a signal corresponding to the highest of the output signals of all of said amplifiers; c. first feedback means connected between said common output and the input of each of said amplifiers for continuously applying to each said amplifier an inverted input signal whose amplitude is a predetermined fraction of the signal appearing at said common output; d. a plurality of second feedback means, each of said second feedback means being connected between the output and the input of a respective amplifier and including a switching means, for selectively applying an inverted input signal, whose amplitude is a predetermined fraction of the output signal of the respective amplifier, to the input of the respective amplifier only if the output signal thereof is not said highest output signal of all of said amplifiers, so that the total feedback signal applied to the input of the amplifier having the highest output signal has an amplitude which is a predetermined fraction of said signal at the common output and the feedback signal applied to the input of each of the other amplifiers have an amplitude which is equal to the sum of the feedback signal which is a predetermined fraction of the signal at said common output and the feedback signal which is a predetermined fraction of the respective amplifier output; and e. means connected to the output of each of said amplifiers for providing an output signal from the one of said aMplifiers which has the highest input signal which is substantially equal to the output signal thereof, and for providing an output signal from each of the other of said amplifiers which is approximately equal to the difference between its associated input signal and the highest input signal.

Claim 12

In a system including a plurality of conductors each carrying a respective signal, a circuit for providing an indication of which conductor is presently carrying that signal whose amplitude is the highest of all the signals, said circuit comprising in combination: a. a plurality of amplifiers, one for each conductor, each having an input connected to a respective conductor; b. maximum signal value receiving means connected to the outputs of all of said amplifiers and having a common output at which appears a signal corresponding to the highest of the output signals of all of said amplifiers; c. first feedback means connected between said common output and the input of each of said amplifiers for continuously applying to each said amplifier an inverted input signal whose amplitude is a predetermined fraction of the signal appearing at said common output; d. a plurality of second feedback means, each of said second feedback means being connected between the output and the input of a respective amplifier and including a switching means, for selectively applying an inverted input signal, whose amplitude is a predetermined fraction of the output signal of the respective amplifier, to the input of the respective amplifier only if the output signal thereof is not said highest output signal of all of said amplifiers, so that the total feedback signal applied to the input of the amplifier having the highest output signal has an amplitude which is a predetermined fraction of said signal at the common output and the feedback signal applied to the input of each of the other amplifiers have an amplitude which is equal to the sum of the feedback signal which is a predetermined fraction of the signal at said common output and the feedback signal which is a predetermined fraction of the respective amplifier output; and e. means connected to the output of each of said amplifiers for providing an output signal from the one of said aMplifiers which has the highest input signal which is substantially equal to the output signal thereof, and for providing an output signal from each of the other of said amplifiers which is approximately equal to the difference between its associated input signal and the highest input signal.

Claim 13

The arrangement as defined in claim 10 wherein said first feedback means and each of said plurality of second feedback means are connected to form a like plurality of signal summing circuits, the outputs of which are connected to the inputs of the respective amplifiers.