Current source with internal variable resistance and control loop for reduced process sensitivity
AssigneeIntel Corporation
InventorsAmaresh Pangal, Siva G. Narendra, Aaron K. Martin, Stephen R. Mooney
Life of this patent
Estimating the term…
Abstract
A current reference with reduced sensitivity to process variations includes two current sources. The first current source has an output current that is sensitive to process variations. The second current source has, as a component of its input current, the output current of the first current source. The input current to the second current source is substantially constant because the process dependent component has been removed by the output current of the first current source. Variable resistors internal to the current source are set using a control loop circuit and an external resistor.
Claims30
A current reference comprising:
- a first current source having an output node to produce an output current that varies with process variations;
- a second current source having an input node to receive an input current, and an output node to produce a current reference output current, the input node being coupled to the output node of the first current source, such that the output current of the first current source influences the current reference output current;
- a variable resistor coupled to the input node of the second current source;
- and
- a control loop circuit to influence the variable resistor.
A current reference comprising:
- a first current source having an input node and having an output node to produce an output current that varies with process variations;
- a second current source having an input node to receive an input current, and an output node to produce a current reference output current, the input node being coupled to the output node of the first current source, such that the output current of the first current source influences the input current of the second current source;
- a voltage divider circuit coupled to the input node of the first current source, the voltage divider circuit including variable resistors;
- and
- a control loop circuit to influence the variable resistors.
A current reference comprising:
- a voltage reference;
- a first current source having an input node coupled to the voltage reference, and having an output node;
- and
- a second current source having a second input node and a second output node, wherein the second input node is coupled to the voltage reference and is coupled to the output node of the first current source, such that a current on the output node of the first current source influences an output current on the second output node;
- a series resistor coupled between the voltage reference and the second input node;
- and
- a control loop circuit to modify a resistance value of the series resistor.
An integrated circuit comprising:
- a first current source with an input node to receive an input current and an output node to produce an output current that varies with process variations;
- a voltage reference to supply a generated current that includes a substantially constant component and a process dependent component, the process dependent component being substantially equal to the output current of the first current source;
- a second current source having an input node coupled to both the output node of the first current source and the voltage reference, such that an input current on the input node of the second current source is equal to the substantially constant component;
- a variable series resistor coupled between the voltage reference and the input node of the second current source;
- and
- a control loop circuit to modify a resistance value of the variable resistor.
Dependencies are inferred from the claim text.