Method of determining DC-DC converter losses and a DC-DC converter employing same

A controller for a power supply for supplying a DC bus voltage to a plurality of DC-DC switching converters, wherein the controller is configured to control at least one switching circuit providing the DC bus voltage from an input voltage, wherein the controller is configured to receive a measure of efficiency, representing the ratio between power output and power input, and/or power loss, representing the difference between power input and power output, value from each of the plurality of DC-DC switching converters and wherein the controller is further configured to adjust the bus voltage in response to the received power loss values to minimize overall power loss for the plurality of DC-DC switching converters.

A switching DC-DC converter comprising:

• at least one switching circuit for converting an input voltage to an output voltage,
• a controller having a control loop for controlling the operation of the switching circuit, the controller having an auto-zero loop for modifying a feedback gain to reduce error in the control loop, and
• a loss estimator adapted to estimate a power loss corresponding to a difference between input power to and output power from the at least one switching circuit from the value of feedback gain.

A switching DC-DC converter comprising:

• at least one switching circuit for converting an input voltage to an output voltage, the at least one switching circuit having at least two switching phases, wherein the at least one switching circuit is configured to operate in a first mode or a second mode where the modes are differentiated by the combination of switching phases employed, a controller, the controller having a control loop for controlling the at least one switching circuit and an auto-zero loop estimator for minimizing the loop error in the control loop by adjusting a feedback gain value in the control loop,
• an estimator for estimating a first loss value representing a difference between input power to and out output power from the switching circuit when operating in a first mode and a second loss value representing a difference between input power to and output power from the switching circuit when operating in a second mode,
• a mode selector for switching the controller between the first and second modes at a crossover point wherein the mode selector is responsive to the first and second loss values in determining the crossover point.

A digital controller for a switch mode power supply, the digital controller providing at least one switching signal to a switching circuit, the digital controller having one or more signals internally corresponding to one or more operating parameters, the one or more signals being available at a first rate from the controller characterized in that the digital controller comprises:

• a first filter for filtering the at least one parameter to provide a filtered at least one parameter signal,
• a first downsampler for downsampling the filtered at least one parameter signal from the first rate to a second rate to produce a downsampled at least one parameter signal, a communications circuit for communicating the downsampled at least one operating parameter to a device external to the controller.

A DC bus voltage controller being adapted to operate at least one switching circuit to provide a common DC bus voltage to a plurality of switching DC-DC converters, which in turn deliver power locally in one or more circuits, wherein the bus voltage controller is configured to receive a measure of power loss representing a difference between input power to and output power from each of the plurality of DC-DC switching converters, wherein the DC bus controller is adapted to adjust the bus voltage in response to the received power loss measurements.