Multi-zone data converters
View Patent ↗Aspects of a method and system for data converters having a transfer function with multiple operating zones. In some embodiments, an operating zone of the multiple operating zones is characterized by more stringent performance criteria than the other operating zones. Thus, such data converters may receive an input signal and generate an output signal from the input signal per the transfer function and the more stringent performance criteria in the appropriate operating zone.
1. A multi-zone digital-to-analog converter, comprising
a digital input configured to receive a digital input signal;
an analog output configured to output an analog output signal representative of the digital input signal;
a first plurality of current sources associated with a first zone of the digital input signal;
a second plurality of current sources associated with a second zone of the digital input signal; and
a plurality of switches that selectively couple the first plurality of current sources and the second plurality of current sources to the analog output in order to provide the analog output with the analog output signal representative of the digital input signal;
wherein the first plurality of current sources provide the first zone with one or more first performance characteristics;
wherein the second plurality of current sources provide the second zone with one or more second performance characteristics; and
wherein the one or more first performance characteristics provided by the first plurality of current sources are higher than the one or more second performance characteristics provided by the second plurality of current sources.
2. The multi-zone digital-to-analog converter of claim 1 , further comprising a decoder configured to selectively close the plurality of switches based on the digital input signal.
3. The multi-zone digital-to-analog converter of claim 1 , wherein the first zone is below the second zone.
4. The multi-zone digital-to-analog converter of claim 1 , wherein the one or more first performance characteristics of the first zone result in the second plurality of current sources consuming less power than the first plurality of current sources.
5. The multi-zone digital-to-analog converter of claim 1 , wherein the one or more first performance characteristics of the first zone result in the second plurality of current sources being smaller than the first plurality of current sources.
6. The multi-zone digital-to-analog converter of claim 1 , wherein the one or more first performance characteristics of the first zone result in the second plurality of current sources having less accurate matching than the first plurality of current sources.
7. The multi-zone digital-to-analog converter of claim 1 , wherein:
each switch, from the plurality of switches that is associated with a current source from the first plurality of current sources, comprises a transmission gate switch; and
each switch, from the plurality of switches that is associated with a current source from the second plurality of current sources, comprises a single transistor switch.
8. A method of a multi-zone digital-to-analog converter, the method comprising:
receiving a digital input signal with a digital input of the multi-zone digital-to-analog converter;
selectively closing switches from a plurality of switches of the multi-zone digital-to-analog converter based on the digital input signal received by the digital input to selectively couple current sources from a first plurality of current sources and a second plurality of current sources to an analog output of the multi-zone digital-to-analog converter; and
outputting an analog output signal representative of the digital input signal based on the current sources from the first plurality of current sources and the second plurality of current sources coupled to the analog output, wherein the first plurality of current sources provide a first zone of the digital input signal with one or more first performance characteristics, the second plurality of current sources provide a second zone of the digital input signal with one or more second performance characteristics, and the one or more first performance characteristics provided by the first plurality of current sources are higher than the one or more second performance characteristics provided by the second plurality of current sources.
9. The method of claim 8 , wherein said selectively closing comprises a decoder of the multi-zone digital-to-analog converter selectively closing the switches from the plurality of switches based on the digital input signal.
10. The method of claim 8 , wherein said selectively closing comprises selectively coupling, to the analog output, the current sources from the first plurality of current sources and the second plurality of current sources such that the first zone is below the second zone.
11. The method of claim 8 , further comprising consuming less power when the analog output signal is in the second zone than when the analog output signal is in the first zone.
12. The method of claim 8 , wherein said selectively closing comprises selectively coupling, to the analog output, second current sources from the second plurality of current sources that are smaller than first current sources from the first plurality of current sources when receiving the digital input signal in the second zone.
13. The method of claim 8 , wherein said selectively closing comprises selectively coupling, to the analog output, second current sources from the second plurality of current sources that have less accurate matching than first current sources from the first plurality of current sources when receiving the digital input in the second zone.
14. The method of claim 8 , wherein said selectively closing comprises:
selectively closing transmission gate switches from the plurality of switches that are associated with the first plurality of current sources; and
selectively closing single transistor switches from the plurality of switches that are associated with the second plurality of current sources.