Methods and devices for adaptive voltage steadying
AssigneeSTMicroelectronics S.r.l.
InventorsNicola Lupo, Enrico Mammei, Michele Bartolini, Stefano Colli
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Abstract
A method to drive a digital to analog converter (DAC), the method including setting a reference current for the DAC with a reference current source, a base voltage being responsive to changes in a reference voltage at a reference node coupled with the reference current source; sensing a change in the reference voltage; and adaptively steadying the base voltage based on the change in the reference voltage to maintain proportionality between an output current of the DAC and the reference current.
Claims20
A method to drive a digital to analog converter (DAC), the method comprising:
- setting a reference current for the DAC with a reference current source, a base voltage being responsive to changes in a reference voltage at a reference node coupled with the reference current source;
- sensing a change in the reference voltage;
- and
- adaptively steadying the base voltage based on the change in the reference voltage.
A voltage stabilization stage for a digital to analog converter (DAC), the voltage stabilization stage comprising:
- a voltage sensing stage coupled with a reference node to sense a change in a voltage at the reference node, the reference node be coupled with a reference current source;
- a voltage follower coupled with the voltage sensing stage and configured to buffer a voltage signal, the voltage signal depending on the change in the voltage at the reference node;
- and
- an output stage configured to output a base voltage depending on the voltage signal.
An adaptive current driving system, the adaptive current driving system comprising:
- a digital to analog converter (DAC) comprising:
- an input to receive a digital code comprising a number N bits;
- and
- N DAC cells, each of the N DAC cells comprising a bipolar transistor, and each of the N DAC cells being configured to be activated depending on a state of a corresponding bit of the digital code;
- a reference stage comprising a reference bipolar transistor coupled at a collector with a reference current source and being coupled at a base with the bases of the bipolar transistors of the N DAC cells;
- and
- a voltage stabilization stage comprising a voltage sensing stage coupled with a reference node to sense a change in a voltage at the reference node, the reference node being coupled with the collector of the reference bipolar transistor, a voltage follower coupled with the voltage sensing stage and configured to buffer a voltage signal, the voltage signal depending on the change in the voltage at the reference node, and an output stage configured to adaptively steady a base voltage at the base of the reference bipolar transistor depending on the voltage signal.
Dependencies are inferred from the claim text.