Switching systems and methods with current sensing

An electronic circuit comprising a switching regulator configured in a current mode control loop comprising

• a first switching transistor having a first terminal, a second terminal, a control terminal, and a first resistance between the first terminal and the second terminal when the control terminal is in an on state, the first terminal coupled to a first node receiving a first switching current, the second terminal coupled to a reference voltage, and the control terminal coupled to receive a switching signal;
• a second switching transistor having a first terminal coupled to the first terminal of the first switching transistor, a second terminal, a control terminal coupled to the control terminal of the first switching transistor, and a second resistance between the first terminal and the second terminal when the control terminal is in the on state;
• and
• one or more transistors coupled in a first series, each transistor having a first terminal, a second terminal, a control terminal coupled to a bias voltage, and a third resistance between the first terminal and the second terminal,
• wherein a first terminal of an initial transistor in the first series is coupled to the second terminal of the second switching transistor, and a second terminal of a last transistor in the first series is coupled to the reference voltage,
• wherein the first switching current is coupled to a second node between the second terminal of the second switching transistor and the first terminal of the initial transistor in the first series, and in accordance therewith, produces a switching voltage corresponding to said first switching current.

A method comprising:

• receiving a first switching current to be sensed in a first terminal of a first transistor and a first terminal of a second transistor, wherein the first and second transistors each comprise second terminals coupled to a reference voltage;
• receiving a switching control signal in a control terminal of the first transistor and a control terminal of the second transistor, and in accordance therewith, generating a sense current in the second transistor that is a fraction of the first switching current;
• and
• coupling the sense current through a first plurality of series transistors, wherein each transistor in said first plurality of series transistors has a control terminal coupled to a bias voltage, and in accordance therewith, generating a switching voltage corresponding to the first switching current.