Dynamic biasing for regulator circuits
View Patent ↗The disclosed invention provides apparatus and methods for dynamic biasing in electronic systems and circuits. The apparatus and methods disclosed provide non-linear biasing responsive to monitored load conditions.
1. A method for biasing a circuit comprising the steps of:
placing a regulator in the circuit;
providing the regulator with a bias current;
sensing an output current of the circuit;
comparing the sensed output current to a preselected threshold; and
adjusting the bias current using a piecewise linear and non-linear feedback function based on the comparison of the sensed output current with the preselected threshold wherein said adjusted bias current is non-linear with respect to the sensed output current.
2. The method according to claim 1 wherein the step of adjusting the bias current further comprises using a logarithmic function for a portion of the piecewise linear and non-linear feedback function.
3. The method according to claim 1 wherein the step of adjusting the bias current further comprises using a non-linear function that comprises at least one step function for a portion of the piecewise linear and non-linear feedback function.
4. The method according to claim 1 wherein the step of adjusting the bias current further comprises using a continuous piecewise linear and non-linear function.
5. The method according to claim 1 wherein the step of adjusting the bias current further comprises clamping the linear and non-linear function at a maximum value.
6. The method according to claim 1 wherein the step of adjusting the bias current further comprises using a source-degenerated non-linear function for a portion of the piecewise linear and non-linear feedback function.
7. A low-power regulator circuit comprising:
a power input node and a power output node, operably coupling the low-power regulator circuit with an associated system;
a load monitoring component operably coupled for sensing an output current at the output node; and
a biasing component configured for comparing the sensed output current to a preselected threshold, and providing a bias current amplitude that is a linear and non-linear function of the comparison of the sensed output current with the preselected threshold wherein said bias current amplitude is linear and non-linear with respect to the sensed output current.
8. A circuit according to claim 7 wherein the biasing component compares the sensed output current to a plurality of preselected thresholds.
9. A circuit according to claim 7 wherein the biasing component is configured to provide a bias current that is linear based on a first comparison of a first threshold and a first sensed output current, and to provide a bias current that is non-linear based on a second comparison of a second threshold and a second sensed output current.
10. A circuit according to claim 7 wherein the load monitoring component further comprises a current sensing module.
11. A circuit according to claim 7 wherein the biasing component further comprises a threshold detecting module.
12. A circuit according to claim 7 wherein the biasing component further comprises a feedback function module.
13. The low-power regulator circuit of claim 7 wherein the biasing component further comprises:
a current sensing circuit configured to generate a current sense output;
a threshold detection circuit configured to receive the current sense output and to generate a threshold detect output;
a feedback function circuit configured to receive the threshold detect output and to generate a feedback function output;
an amplifier coupled to the power input node, the power output node, a reference voltage and the feedback function circuit; and
a transistor having a first terminal coupled to the power input node, a control terminal coupled to the amplifier and a second terminal coupled to the power output node.
14. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that is linear and a second output range that is non-linear.
15. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that is linear and a continuous second output range that is non-linear.
16. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that is linear and a second output range that is logarithmic.
17. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that is linear and a second output range that is asymptotic.
18. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that is linear and a second output range that is a step function.
19. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that has a first linear response, a second output range that has a second linear response that is different from the first linear response and a third output range that is non-linear.
20. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that has a first linear response, a second output range that has a second linear response that is different from the first linear response and a third output range that is a step function.
21. The low-power regulator of claim 7 wherein the linear and non-linear function comprises a first output range that has a first linear response, a second output range that has a second linear response that is different from the first linear response and a third output range that is logarithmic.