Power regulation circuit for droop mitigation in a power source voltage that powers a processing core
Embodiments of a power regulation circuit that ameliorates a first and second droop in a power source voltage that powers a processing core are disclosed. The power regulation circuit includes a first droop detector, a second droop detector and a frequency slowdown detection circuit. The first droop detector generates a first droop detection signal in a first detection state in response to detecting a first droop in the power source voltage. The second droop detector generates a second droop detection signal in a second detection state in response to detecting a second droop in the power source voltage. The frequency slowdown detection circuit to generate a frequency slowdown signal in a slowdown state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state.
1 . A power regulation circuit for a power source voltage that powers a processing core, the power regulation circuit comprising:
a first droop detector to generate a first droop detection signal in a first detection state in response to detecting a first droop in the power source voltage;
a second droop detector to generate a second droop detection signal in a second detection state in response to detecting a second droop in the power source voltage, wherein the second droop occurs after the first droop;
a frequency slowdown detection circuit to generate a frequency slowdown signal in a slowdown state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state,
wherein the frequency slowdown detection circuit comprises: (a) combination logic to receive the first droop detection signal and the second droop detection signal and to generate a droop detection signal in a third detection state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state, and (b) an asynchronous detector to generate the frequency slowdown signal in the slowdown state in response to the droop detection signal being in the third detection state.
2 . The power regulation circuit of claim 1 , wherein the frequency slowdown detection circuit is coupled to a digitally controlled oscillator (DCO), wherein the DCO is to:
generate a core clock signal having a clock signal frequency that sets an operating frequency of the processing core;
slowdown the clock signal frequency in response to the frequency slowdown signal being in the slowdown state.
3 . The power regulation circuit of claim 1 , wherein:
the second droop detector to receive a first threshold voltage having a first threshold voltage level;
the second droop detector comprises a bandpass filter having a passband that is at least partially aligned with a frequency range of the second droop;
the second droop detector to generate the second droop detection signal in the second detection state in response to the bandpass filter filtering the second droop such that the second droop is lower than the first threshold voltage level of the first threshold voltage.
4 . The power regulation circuit of claim 3 , wherein:
the first droop detector to receive a second threshold voltage having a second threshold voltage level;
the first droop detector comprises a highpass filter having a high band that includes a frequency range of the first droop;
the first droop detector to generate the first droop detection signal in the first detection state in response to the highpass filter filtering the first droop such that the first droop is lower than the second threshold voltage level of the second threshold voltage.
5 . The power regulation circuit of claim 1 , wherein the first detection state, the second detection state, and the third detection state are a same voltage state.
6 . The power regulation circuit of claim 1 , wherein the power source voltage is received from a power rail.
7 . An apparatus, comprising:
a power rail configured to receive a power source voltage;
a processing core that is powered by the power source voltage;
a digitally controlled oscillator (DCO) to generate a core clock signal having a clock signal frequency that sets an operating frequency of the processing core;
a power regulation circuit, comprising:
a first droop detector to generate a first droop detection signal in a first detection state in response to detecting a first droop in the power source voltage, wherein the first droop detector comprises a high pass filter having a high band that includes a frequency range of the first droop;
a second droop detector to generate a second droop detection signal in a second detection state in response to detecting a second droop in the power source voltage, wherein the second droop occurs after the first droop; and
a frequency slowdown detection circuit to generate a frequency slowdown signal in a slowdown state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state, wherein the DCO is to slowdown the clock signal frequency in response to the frequency slowdown signal being in the slowdown state.
8 . The apparatus of claim 7 , wherein:
the second droop detector to receive a first threshold voltage having a first threshold voltage level;
the second droop detector comprises a bandpass filter having a passband that is at least partially aligned with a frequency range of the second droop;
the second droop detector to generate the second droop detection signal in the second detection state in response to the passband filtering the second droop such that the second droop is lower than the first threshold voltage level of the first threshold voltage.
9 . The apparatus of claim 7 , wherein the power source voltage is generated by a battery.
10 . The apparatus of claim 7 , wherein the frequency slowdown detection circuit comprises:
combination logic to receive the first droop detection signal and the second droop detection signal and to generate a droop detection signal in a third detection state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state;
an asynchronous detector to generate the frequency slowdown signal in the slowdown state in response to the droop detection signal being in the third detection state.
11 . The apparatus of claim 10 , wherein the first detection state, the second detection state, and the third detection state are a same voltage state.
12 . A power regulation circuit for a power source voltage that powers a processing core, the power regulation circuit comprising:
a first droop detector to pass a high band so as to detect a first droop in a power source voltage and generate a first droop detection signal in a first detection state in response to detecting the first droop;
a second droop detector to pass a passband to generate a second droop detection signal in a second detection state in response to detecting the second droop in the power source voltage, wherein the second droop occurs after the first droop; and
a frequency slowdown detection circuit to generate a frequency slowdown signal in a slowdown state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state.
13 . The power regulation circuit of claim 12 , wherein the frequency slowdown detection circuit is coupled to a digitally controlled oscillator (DCO), wherein the DCO is to:
generate a core clock signal having a clock signal frequency that sets an operating frequency of the processing core;
slowdown the clock signal frequency in response to the frequency slowdown signal being in the slowdown state.
14 . The power regulation circuit of claim 12 , wherein:
the second droop detector to receive a first threshold voltage having a first threshold voltage level;
the second droop detector comprises a bandpass filter having the passband that is at least partially aligned with a frequency range of the second droop;
the second droop detector to generate the second droop detection signal in the second detection state in response to the bandpass filter filtering the second droop such that the second droop is lower than the first threshold voltage level of the first threshold voltage.
15 . The power regulation circuit of claim 14 , wherein:
the first droop detector to receive a second threshold voltage having a second threshold voltage level;
the first droop detector comprises a highpass filter having the high band that includes a frequency range of the first droop;
the first droop detector to generate the first droop detection signal in the first detection state in response to the highpass filter filtering the first droop such that the first droop is lower than the second threshold voltage level of the second threshold voltage.
16 . The power regulation circuit of claim 12 , wherein the frequency slowdown detection circuit comprises:
combination logic to receive the first droop detection signal and the second droop detection signal and to generate a droop detection signal in a third detection state in response to at least one of the first droop detection signal being in the first detection state and the second droop detection signal being in the second detection state;
an asynchronous detector to generate the frequency slowdown signal in the slowdown state in response to the droop detection signal being in the third detection state.
17 . The power regulation circuit of claim 16 , wherein the first detection state, the second detection state, and the third detection state are a same voltage state.
18 . The power regulation circuit of claim 12 , wherein the power source voltage is received from a power rail.