A high voltage floating current sense amplifier circuit, including first and second resistive devices and a floating amplifier circuit, that senses current through a current sense device coupled between an output node and a battery node each referenced to a common node. The battery node couples to a positive terminal of a removable battery. The floating amplifier circuit drives a proportional current through the first resistor in order to maintain voltage across the first resistive device at approximately the same voltage as that across the current sense device. The second resistive device has a first end coupled to the common node and a second end coupled to receive the proportional current for developing a sense voltage indicative of current through the current sense device.