A Novel Input-Side Current Sensing Method to Achieve AVP for Future VRs

This paper begins with a review of different current sensing methods for the voltage regulator (VR) to achieve adaptive voltage position (AVP). These methods are either inaccurate or with high power consumption for current sensing. Next, a new input-side current sensing method for AVP is proposed. The basic idea of the proposed method is to sense the average input current, which results in low power dissipation for current sensing. Meanwhile, a compensation circuit is proposed to eliminate current sensing errors due to input and output voltage variations. As a result, both low power dissipation and good current sensing accuracy can be achieved by applying the proposed method. The transient and tolerance analysis of this method are provided and a design guideline is illustrated and experimentally verified.