DC-DC voltage converter
A DC-DC voltage converter is provided that includes a plurality of power channels and a controller. Each power channel is configured to provide a voltage output to an output node of the converter. Each power channel also includes a first sensing circuit configured to provide a primary feedback signal indicative of an output current of the power channel. Each power channel further includes an auxiliary sensing circuit to provided one or more auxiliary feedback signals indicative of an output current of each of the respective other power channels. The controller is configured to control each of the power channels based at least in part on the primary feedback signal and the one or more auxiliary feedback signals.
1. A method of operating a multi-channel DC-to-DC converter, the method comprising:
determining a primary output current for each channel in the converter;
for each channel further determining a secondary sensed current for each of the other different channels in the converter; and
using the determined primary output and the secondary sensed currents to control switching elements in channels of the converter, wherein balanced control of all of the channels in the multi-channel DC-to-DC converter is achieved.
2. The method of claim 1 , wherein using the determined primary output and the secondary sensed currents to control switching elements in channels of the converter, further comprises:
averaging the primary output and the secondary sensed currents;
determining a difference between the determined average and the primary output current;
subtracting the determined difference from a determined error voltage; and
using an outcome of the subtraction to control the switching elements.
3. The method of claim 2 , further comprises:
determining the error voltage by comparing an output voltage of the converter to a reference voltage.
4. The method of claim 2 , wherein using an outcome of the subtraction to control the switching elements further comprises:
controlling a modulator with a signal based on the subtraction; and
controlling a driver that controls the switching elements with an output of the modulator.
5. The method of claim 2 , wherein using an outcome of the subtraction to control the switching elements further comprises:
modulating an output signal based on the subtraction; and
driving driver logic that controls the switching elements with the modulated output signal.
6. The method of claim 1 , wherein determining the primary output current for each channel in the converter further comprises:
sensing a current on a common node of a primary resistor and a capacitor that are coupled across an inductor of the channel.
7. The method of claim 6 , wherein for each channel further determining a secondary sensed current for each of the other different channels in the converter further comprises:
sensing a current through an auxiliary resistor coupled to an output node of the converter, the auxiliary resistor the having the same value as the primary resistor.