Multi-phase power converter with external phase circuits
Various embodiments for generating a voltage level on a regulated power supply node are disclosed. In one embodiment, an apparatus includes an external phase circuit on a first integrated circuit, where the external phase circuit is coupled to a regulated power supply node via a first inductor and configured to source a first current to the regulated power supply node using an external demand current and in response to an activation of a first enable signal. The apparatus also includes a control circuit on a second integrated circuit, where the control circuit is configured to generate the external demand current using a voltage of the regulated power supply node and a reference voltage. The control circuit is further configured to generate the first enable signal using a sensed version of the first current.
1 . An apparatus, comprising:
an external phase circuit included on a first integrated circuit, wherein the external phase circuit is coupled to a regulated power supply node via a first inductor, wherein the external phase circuit is configured, in response to an activation of a first enable signal, to source a first current to the regulated power supply node using an external demand current;
a control circuit included on a second integrated circuit, wherein the control circuit is configured to:
generate the external demand current using a voltage of the regulated power supply node and a reference voltage; and
generate the first enable signal using a sensed version of the first current.
2 . The apparatus of claim 1 , further comprising an internal phase circuit included on the second integrated circuit, wherein the internal phase circuit is coupled to the regulated power supply node via a second inductor, and wherein the internal phase circuit is configured, in response to an activation of a second enable signal, to source a second current to the regulated power supply node using an internal demand current.
3 . The apparatus of claim 2 , wherein the control circuit is further configured to:
generate the internal demand current using the voltage of the regulated power supply node and the reference voltage; and
generate the second enable signal using a sensed version of the second current.
4 . The apparatus of claim 3 , wherein to generate the first enable signal, the control circuit is further configured to perform a first comparison of the sensed version of the first current to a first current threshold, and wherein to generate the second enable signal, the control circuit is further configured to perform a second comparison of the sensed version of the second current to a second current threshold.
5 . The apparatus of claim 2 , wherein a first switching frequency of the external phase circuit is less than a second switching frequency of the internal phase circuit.
6 . The apparatus of claim 1 , wherein to source the first current, the external phase circuit is further configured to perform a comparison of the external demand current and the sensed version of the first current.
7 . A method, comprising:
sourcing, by an external phase circuit in response to an activation of a first enable signal and using an external demand current, a first current to a regulated power supply node via a first inductor, wherein the external phase circuit is included on a first integrated circuit;
generating, by a control circuit, the external demand current using a voltage of the regulated power supply node and a reference voltage, wherein the control circuit is included on a second integrated circuit; and
generating, by the control circuit, the first enable signal using a sensed version of the first current.
8 . The method of claim 7 , further comprising sourcing, by an internal phase circuit in response to an activation of a second enable signal and using an internal demand current, a second current to the regulated power supply node via a second inductor, wherein the internal phase circuit is included on the second integrated circuit.
9 . The method of claim 8 , further comprising:
generating, by the control circuit, the internal demand current using the voltage of the regulated power supply node and the reference voltage; and
generating, by the control circuit, the second enable signal using a sensed version of the second current.
10 . The method of claim 9 , wherein generating the first enable signal includes performing, by the control circuit, a first comparison of the sensed version of the first current to a first current threshold, and wherein generating the second enable signal including performing, by the control circuit, a second comparison of the sensed version of the second current to a second current threshold.
11 . The method of claim 9 , wherein sourcing the second current includes performing, by the internal phase circuit, a comparison of the internal demand current and the sensed version of the second current.
12 . The method of claim 8 , wherein a first switching frequency of the external phase circuit is less than a second switching frequency of the internal phase circuit.
13 . The method of claim 7 , wherein sourcing the first current includes performing, by the external phase circuit, a comparison of the external demand current and the sensed version of the first current.
14 . An apparatus, comprising:
a first external phase circuit coupled to a first regulated power supply node via a first inductor, wherein the first external phase circuit is configured, based on a first plurality of control signals, to source a first current to the first regulated power supply node using a first input power supply node;
a second external phase circuit coupled to the first regulated power supply node via a second inductor, wherein the second external phase circuit is configured, based on a second plurality of control signals, to source a second current to the first regulated power supply node using a second input power supply node; and
a first control circuit configured to generate the first plurality of control signals and the second plurality of control signals.
15 . The apparatus of claim 14 , further comprising:
a third external phase circuit coupled to a second regulated power supply node via a third inductor, wherein the third external phase circuit is configured, based on a third plurality of control signals, to source a third current to the second regulated power supply node using the first input power supply node; and
a second control circuit configured to generate the third plurality of control signals.
16 . The apparatus of claim 15 , wherein the second control circuit includes an internal phase circuit coupled to the second regulated power supply node via a fourth inductor, and wherein the internal phase circuit is configured, in response to an activation of an enable signal, to source a fourth current to the second regulated power supply node using an internal demand current.
17 . The apparatus of claim 16 , wherein a first switching frequency of the third external phase circuit is less than a second switching frequency of the internal phase circuit.
18 . The apparatus of claim 14 , wherein a voltage level of the second input power supply node is greater than a voltage level of the first input power supply node.
19 . The apparatus of claim 14 , wherein the first controller circuit and second controller circuit are located on a first integrated circuit, and at least one of the first external phase circuit or second external phase circuit is located on a second integrated circuit.
20 . The apparatus of claim 14 , wherein the first external phase circuit is further configured to:
source the first current to the first regulated power supply node during a first on-time period; and
source, via a third inductor, a third current to the first regulated power supply node during a second on-time period different than the first on-time period.