Load sensing circuit employing sink and sense configuration

A method comprising:

• applying a load voltage to a load to produce a load signal that flows through the load to a regulated sink circuit coupled to a sink voltage, wherein the load signal has a first electrical characteristic and a second electrical characteristic, and wherein the load has a load characteristic;
• applying the load signal to a sense input of a comparison circuit, wherein the load signal establishes a sense value of the second electrical characteristic;
• applying a reference signal to a reference input of the comparison circuit, wherein the reference signal includes one or more oscillating components and establishes a reference value of the second electrical characteristic;
• generating a comparison signal indicating a difference between the sense value of the second electrical characteristic and the reference value of the second electrical characteristic;
• regulating a value of the first electrical characteristic of the load signal using the regulated sink circuit to vary the value of the first electrical characteristic so that the sense value of the second electrical characteristic matches the reference value of the second electrical characteristic;
• converting the comparison signal to a digital signal;
• and
• sensing changes in the load characteristic based on the digital signal.

A load-sensing circuit comprising:

• an external load connection configured to receive a load signal when coupled to an external load, the load signal generated by applying a drive signal having a load voltage to the external load, and wherein the load signal has a first electrical characteristic and a second electrical characteristic;
• a comparison circuit including:
• a sense input coupled to the external load connection, wherein the load signal establishes a sense value of the second electrical characteristic;
• a reference input coupled to a reference signal circuit wherein the reference signal circuit establishes a reference value of the second electrical characteristic, the reference value including one or more oscillating components;
• and
• a comparison output configured to generate a comparison signal indicating a difference between the sense value of the second electrical characteristic and the reference value of the second electrical characteristic;
• a feedback circuit coupled to the comparison output, and configured to generate a regulation signal based on the comparison signal;
• an analog to digital converter configured to convert the comparison signal to a digital comparison signal;
• and
• a regulated sink circuit including;
• an external sink output configured to be connected to a sink voltage;
• a load signal input coupled to the external load connection and to the sense input of the comparison circuit;
• and
• a regulation input configured to receive the regulation signal, wherein the regulated sink circuit is configured to regulate the first electrical characteristic of the load signal, based on the regulation signal, so that the sense value of the second electrical characteristic matches the reference value of the second electrical characteristic.