Voltage-based auto-correction of switching time

1. A control device for a switching voltage regulator having a switching module to supply a switching voltage to a load, the control device comprising:

a comparator configured to compare the switching voltage with a reference voltage to provide a disable signal to the switching module; and

a spike detection circuit configured to receive the switching voltage and output an offset control signal to execute a time shift to the disable signal,

wherein the spike detection circuit comprises a first input coupled to the switching voltage, a second input coupled to a threshold voltage, and an output for providing the offset control signal to the comparator.

2. The control device of claim 1 , wherein the comparator is a differential operational amplifier having a first input coupled to the switching voltage, a second input coupled to the reference voltage, a third input coupled to the offset control signal of the spike detection circuit, and an output for providing the disable signal to the switching module.

3. The control device of claim 2 , wherein the differential operational amplifier comprises:

a variable resistive element with an equivalent resistance determined by an analog control signal; or

a resistor array with an equivalent resistance determined by a digital word.

4. The control device of claim 3 , wherein the spike detection circuit comprises:

a first differential operational amplifier for detecting a positive glitch associated with a first off time of the disable signal;

a second differential operational amplifier for detecting a negative glitch associated with a second off time of the disable signal;

a logic circuit coupled to the first and second differential operational amplifiers and configured to provide an indication signal indicating a presence of a glitch and whether the glitch is a positive glitch or a negative glitch.

5. The control device of claim 4 , wherein the spike detection circuit further comprises a digital-to-analog converter configured to convert the indication signal to an analog signal for adjusting a resistive value of the variable resistive element.

6. The control device of claim 1 , wherein the switching module comprises a high-side switch being a p-channel transistor, and a low-side switch being an n-channel transistor.

7. A switching regulator comprising:

a controller for providing a first driver signal and a second driver signal;

a dead-time control circuit comprising a first input terminal connected to the first driver signal, a second input terminal connected to the second driver signal, a first output terminal, and a second output terminal;

a switching module coupled to the first and second out terminals and configured to supply a switching voltage to an LC network; and

a spike detection circuit configured to receive the switching voltage and provide a control signal to the dead-time control circuit.

8. The switching regulator of claim 7 , wherein the dead-time control circuit comprises:

two cross-coupled logic gates including a first logic gate having a first input connected to the first input terminal, a second input, and a first output, a second logic gate having a third input connected to the second input terminal, a fourth input, and a second output;

a first delay element having a fifth input connected to the second output of the second logic gate and a third output connected to the second input of the first logic gate;

a second delay element having a sixth input connected to the first output of the first logic gate and a fourth output connected to the second input of the second logic gate.

9. The switching regulator of claim 8 , wherein the switching module comprises:

one or more p-channel transistor and one or more n-channel transistor connected in series between an input voltage signal and ground.

10. The switching regulator of claim 8 , wherein the first and second logic gates are not a same type logic gate.

11. The switching regulator of claim 8 , wherein the first delay element and the second delay element each comprise an RC element or a cascaded delay stage having a plurality of variable delay units.

12. The switching regulator of claim 11 , wherein the RC element comprises a variable resistive element.

13. The switching regulator of claim 12 , wherein the variable resistive element comprises a metal oxide semiconductor (MOS) transistor or a field effect transistor.

14. The switching regulator of claim 12 , wherein the spike detection circuit comprises:

a differential operational amplifier having a first input for receiving the switching voltage, a second input for receiving a reference voltage, and configured to provide the control signal in response to a difference between the switching voltage and the reference voltage.

15. The switching regulator of claim 14 , wherein the spike detection circuit further comprises an analog-to-digital converter configured to convert the control signal to an analog signal for adjusting a resistance value of the variable resistive element.

16. The switching regulator of claim 11 , wherein the plurality of variable delay units comprises:

an array of switchable capacitor elements; or

current controlled delay cells.

17. A method for controlling a dead time of a switching regulator comprising a switching module and a controller providing first and second driver signals to the switching module, the method comprising:

providing a dead-time control circuit between the controller and the switching module and a spike detection circuit between the switching module and the dead-time control circuit;

monitoring a switching voltage at an output terminal of the switching module by the spike detection circuit;

determining whether the switching voltage exceeds a threshold voltage; and

if the switching voltage exceeds the threshold voltage, generating a control signal to the dead-time control circuit to adjust a dead time between the first driver signal and the second driver signal; and

if the switching voltage does not exceed the threshold voltage, maintaining the dead time between the first driver signal and the second driver signal.

18. The method of claim 17 , wherein the dead-time control circuit comprises:

two cross-coupled logic gates including a first logic gate having a first input for receiving the first driver signal, a second input, and a first output, a second logic gate having a third input for receiving the second driver signal, a fourth input, and a second output;

a first delay element having a fifth input connected to the second output of the second logic gate and a third output connected to the second input of the first logic gate; and

a second delay element having a sixth input connected to the first output of the first logic gate and a fourth output connected t the second input of the second logic gate.

19. The method of claim 17 , wherein determining whether the switching voltage exceeds a threshold voltage comprises:

comparing the switching voltage with a threshold voltage to obtain the control signal; and

converting the control signal to an analog signal for adjusting the dead time.

20. The method of claim 19 , further comprising:

iteratively monitoring the switching voltage, comparing the switching voltage with the threshold voltage, and adjusting the dead time until the switching voltage is lower than first threshold voltage.