Digital to analog converter and a ground offset compensation circuit
AssigneeAnalog Devices, Inc.
InventorsAlan Gillespie, Roderick C. McLachlan, Teng-Hee Lee
Life of this patent
Estimating the term…
Abstract
A digital to analog converter comprising: a digital to analog conversion core adapted to receive at least one reference voltage and a digital word to be converted, and to output an analog voltage as a function of the digital word and the at least one reference voltage; a sensing circuit for sensing a difference between a first ground voltage associated with an output of the digital to analog converter and a ground reference voltage occurring at the digital to analog converter; and a compensation circuit for applying a compensation voltage to the at least one reference voltage used by the conversion core of the digital to analog converter.
Claims24
A digital to analog converter comprising:
- a) a digital to analog conversion core adapted to receive at least one reference voltage and a digital word to be converted, and to output an analog voltage as a function of the digital word and the at least one reference voltage;
- b) a sensing circuit for sensing a difference between a first ground voltage associated with an output of the digital to analog converter and a ground reference voltage occurring at the digital to analog converter;
- and
- c) a compensation circuit for applying a compensation voltage to the at least one reference voltage used by the conversion core of the digital to analog converter.
A reference circuit for supplying reference voltages, the reference circuit comprising a reference voltage generator for generating at least one reference voltage and a compensation circuit responsive to a first voltage and to a second voltage, and to offset the at least one reference voltage as a function of a difference between the first and second voltages, wherein the first voltage is a ground voltage occurring at the reference circuit and the second voltage is a ground voltage occurring in a further circuit.
A method of operating a digital to analog converter comprising the steps of:
- a. Forming a difference value between a ground voltage occurring at a reference voltage generator used to supply a reference voltage to a conversion core of the digital to analog converter and a ground voltage occurring at a device driven by the digital to analog converter;
- and
- b. Applying that difference value to the digital to analog converter such that an output of the digital to analog converter is modified by the difference value.
A digital to analog converter comprising:
- a) a plurality of digital to analog conversion cores receiving at least one reference voltage and a respective digital to word to be converted, and to output respective analog voltages as a function of the respective digital word and the at least one reference voltage, said cores having respective output ground terminals;
- b) a plurality of sensing circuits for sensing respective voltage differences between a ground reference voltage occurring at the digital to analog converter and ground voltages occurring at output ground terminals of the respective digital to analog conversion cores;
- and
- c) a plurality of compensation circuits for applying a compensation voltage to the at least one reference voltage used by a respective digital to analog conversion core so as to compensate for the respective voltage differences.
A digital to analog converter having a voltage output at a first output thereof and an output ground, the digital to analog converter comprising:
- a. a digital to analog conversion core adapted to receive at least one reference voltage and a digital word to be converted, and to output an analog voltage as a function of the digital word and the at least one reference voltage;
- b. a sensing circuit for sensing a difference between a first ground voltage occurring at the output ground and a ground reference voltage occurring at the digital to analog converter;
- and
- c. a compensation circuit for applying a compensation voltage to the at least one reference voltage used by the conversion core of the digital to analog converter, the compensation voltage being formed from the difference between the first ground voltage occurring at the output ground and the ground reference voltage occurring at the digital to analog converter.
A reference circuit for supplying reference voltages to a resistive potential divider, the reference circuit comprising a reference voltage generator for generating at least one reference voltage and a compensation circuit responsive to a first voltage and to a second voltage, and to offset the at least one reference voltage as a function of a difference between the first and second voltages, wherein the first voltage is a ground voltage occurring at the reference circuit and the second voltage is a ground voltage occurring in a further circuit.
Dependencies are inferred from the claim text.