APPARATUS AND METHOD FOR MEASURING LOAD CURRENT BY APPLYING COMPENSATED GAIN TO VOLTAGE DERIVED FROM DRAIN-TO-SOURCE VOLTAGE OF POWER GATING DEVICE

摘要

Apparatus and method are disclosed for measuring a load current supplied to one or more integrated circuit cores. The apparatus includes a power gating field effect transistor (FET) comprising a gate, a source, and a drain, wherein the source is coupled to a voltage rail, wherein the drain is coupled to a load, and wherein the gate is configured to receive a gating voltage to selectively turn on the power gating FET to allow a load current to flow between the voltage rail and the load; and a differential amplifier configured to generate a current-related voltage related to the load current by applying a gain to an input voltage based on a drain-to-source voltage of the power gating FET, wherein the gain varies inversely with the input voltage in response to variation in temperature or gate-to-source voltage of the power gating FET.

主权项

1. An apparatus, comprising:
a power gating field effect transistor (FET) comprising a gate, a source, and a drain, wherein the source is coupled to a voltage rail, wherein the drain is coupled to a load, and wherein the gate is configured to receive a gating voltage to selectively turn on the power gating FET to allow a load current to flow between the voltage rail and the load by way of the power gating FET; and a differential amplifier configured to generate a current-related voltage related to the load current by applying a gain to an input voltage, wherein the input voltage is based on a drain-to-source voltage of the power gating FET, and wherein the gain varies inversely with the input voltage in response to variation in temperature or gate-to-source voltage of the power gating FET.