Segment analog-to-digital or digital-to-analog converter

Claim 2

A segment-type decoder for decoding a digital signal comprising, in combination, a linear decoder component to which a first predetermined portion of said digital signal is applied to generate a current in accordance with that first predetermined portion of said digital signal, first apparatus responsive to a second predetermined portion of said digital signal representing the sign of said analog signal to add or subtract predetermined currents from the output of said linear decoder component in accordance with whether said second predetermined portion indicates that the digital signal represents a positive or negative analog signal, respectively, an amplifier connected to receive the output current from said first apparatus and having at least two levels of gain which levels are determinEd in accordance with a third predetermined portion of said digital input signal, and second apparatus responsive to said second predetermined portion of said digital signal to add or subtract predetermined currents from the output of said amplifier in accordance with whether said second predetermined portion of said digital signal indicates that the digital signal represents a negative or positive analog signal, respectively.

Claim 3

A segment-type encoder for encoding an analog signal comprising, in combination, a digital-to-analog converter which converter comprises, a linear decoder component to which a first portion of a digital signal is applied to generate a current in accordance with that portion of the digital signal, first apparatus responsive to a second portion of the digital signal to add or subtract predetermined currents from the output of said linear decoder component in accordance with whether said second portion of the digital signal indicates that the digital signal represents a positive or negative analog signal, respectively, an amplifier connected to receive the output current from said first apparatus and having at least two levels of gain which are determined in accordance with a third portion of the digital input signal, and second apparatus responsive to the second portion of the digital signal to add or subtract predetermined currents from the output of said amplifier in accordance with whether the second portion indicates that the digital signal represents a negative or positive analog signal, respectively, a comparator connected to receive the output of said digital-to-analog converter and said analog input signal to be encoded, programming means connected to receive the output signal from said comparator, and a digital register, said digital register and said programming means operating to sequentially make successive approximations and generate said digital signals so that the output of said digital register represents the digital output signal.

Claim 4

A segment-type encoder for encoding an analog signal comprising, in combination, a digital-to-analog converter which converter comprises, a linear decoder component to which a first portion of a digital signal is applied to generate a current in accordance with that portion of the digital signal, first apparatus responsive to a second portion of the digital signal to add or subtract predetermined currents from the output of said linear decoder component in accordance with whether said second portion of the digital signal indicates that the digital signal represents a positive or negative analog signal, respectively, an amplifier connected to receive the output current from said first apparatus and having at least two levels of gain which are determined in accordance with a third portion of the digital input signal, and second apparatus responsive to the second portion of the digital signal to add or subtract predetermined currents from the output of said amplifier in accordance with whether the second portion indicates that the digital signal represents a negative or positive analog signal, respectively, a comparator connected to receive the output of said digital-to-analog converter and said analog input signal to be encoded, programming means connected to receive the output signal from said comparator, and a digital register, said digital register and said programming means operating to sequentially make successive approximations and generate said digital signals so that the output of said digital register represents the digital output signal.

Claim 5

A segment-type decoder for converting a digital signal to an analog signal comprising, in combination, a linear decoder component having binary weighted networks to which are connected a positive reference voltage source and a negative reference voltage source, each said network being operated in accordance with the state of a particular bit of a first predetermined portion of said digital signal to generate a current in accordance with that portion of said digital signal, a resistor, and a switch connected to the output of said linear decoder component, said switch being operated in accordance with a second portion of said digital input signal which represents the sign of said analog signal to apply said positive reference voltage to said resistor when said signal represents a positive analog signal and negative reference voltage to said resistor when said signal represents a negative analog signal, a first summing network to sum the output of said linear decoder component and said current obtained from said resistor, an amplifier connected to receive the output current from said first summing network and having at least two levels of gain which are determined in accordance with a third predetermined portion of said digital input signal, a second summing network connected to receive the output of said switched amplifier and having a second input terminal, a resistor and a switch connected in series to said second input terminal of said second summing network said switch having two poles, a first pole connected to said first source of reference voltage and a second pole connected to a second source of said reference voltage so that when the sign bit is positive a predetermined current is subtracted from the output of said switched amplifier and when said predetermined current is negative a current is added to the output of said switched amplifier.

Claim 6

A segment-type decoder for converting a digital signal to an analog signal comprising, in combination, a linear decoder component having binary weighted networks to which are connected a positive reference voltage source and a negative reference voltage source, each said network being operated in accordance with the state of a particular bit of a first predetermined portion of said digital signal to generate a current in accordance with that portion of said digital signal, a resistor, and a switch connected to the output of said linear decoder component, said switch being operated in accordance with a second portion of said digital input signal which represents the sign of said analog signal to apply said positive reference voltage to said resistor when said signal represents a positive analog signal and negative reference voltage to said resistor when said signal represents a negative analog signal, a first summing network to sum the output of said linear decoder component and said current obtained from said resistor, an amplifier connected to receive the output current from said first summing network and having at least two levels of gain which are determined in accordance with a third predetermined portion of said digital input signal, a second summing network connected to receive the output of said switched amplifier and having a second input terminal, a resistor and a switch connected in series to said second input terminal of said second summing network said switch having two poles, a first pole connected to said first source of reference voltage and a second pole connected to a second source of said reference voltage so that when the sign bit is positive a predetermined current is subtracted from the output of said switched amplifier and when said predetermined current is negative a current is added to the output of said switched amplifier.

Claim 7

A segment-type encoder for encoding an analog signal comprising, in combination, the segment-type decoder defined in claim 3, and further comprising a compArator connected to receive the output of said decoder and the analog input signal to be encoded, programming means connected to receive the output signal from said comparator, and a digital register said digital register and said programming means operating to sequentially make successive approximations and generate the digital signals for application to said decoder so that the output of said digital register represents the digital output signal.