Voltage transition technique for a voltage converter

A method of varying a supply voltage that drives a load to a target supply voltage, comprising the steps of:

• generating the supply voltage that is equal to a first voltage;
• receiving a command to vary the supply voltage to a second voltage, the first and second voltage being associated with the target supply voltage set forth to drive the load prior to and subsequent to a supply voltage transition;
• generating a reference voltage, the reference voltage being varied from the first voltage to the second voltage within a supply voltage transition;
• compensating an offset of the reference voltage for a compensated reference voltage, the offset being caused by a voltage drop associated with a local ground of the load;
• introducing a supplemental voltage step into to the compensated reference voltage that is used as a reference to generate the supply voltage;
• varying the compensated reference voltage by a voltage magnitude that is equal to the difference between the first and second voltages;
• controlling the supply voltage to follow the corresponding variation of the compensated reference voltage at a slew rate;
• and
• deducting the supplemental voltage step from the compensated reference voltage when the supply voltage reaches the second voltage, both the compensated reference voltage and the supply voltage settling at the second voltage.

A voltage converter that drives a load with compensation, comprising:

• a reference controller that receives a transition control associated with a target supply voltage needed to drive the load and generates a DAC control signal and a step control signal;
• an internal digital-to-analog converter (DAC), coupled to the reference controller, the internal DAC being controlled by the DAC control signal to generate a reference voltage, the reference voltage being varied from a first voltage to a second voltage within a supply voltage transition, the first and second voltage being associated with the target supply voltage prior to and subsequent to the supply voltage transition, respectively;
• a compensation circuit, coupled between the internal DAC and a switching regulator, the compensation circuit compensating an offset of the reference voltage for a compensated reference voltage, wherein the offset is caused by a voltage drop associated with a local ground of the load;
• the switching regulator, coupled to the internal DAC, the switching regulator generating an output supply voltage that tracks the compensated reference voltage at a slew rate;
• and
• wherein a supplemental voltage step is introduced to the compensated reference voltage under the step control signal during the supply voltage transition and deducted from the compensated reference voltage when the load is driven by the target supply voltage.