Current sense amplifer with extended common mode input voltage range

A current sense system, comprising:

• a resistor coupled in series with a load being monitored, wherein a positive input signal (IN+) voltage is produced at one terminal of the resistor and a negative input signal (IN−) voltage is produced at a second terminal of the resistor, each signal voltage resulting from current flowing through the resistor and the load;
• and
• an extended common mode (CM) input voltage range current sense amplifier comprising a non-inverting input node that receives the IN+ signal and an inverting input node that receives the IN− signal, each input node coupled to opposite terminals of the resistor and the amplifier further comprising:
• a low voltage (LV) p-type metal oxide semiconductor (PMOS) input module coupled to a positive supply rail, wherein said positive supply rail provides a voltage comprising the greater of the IN+ signal voltage applied to the amplifier or an internal power supply voltage;
• and
• a voltage regulator coupled to the positive supply rail that generates a decreased lower voltage level relative to the positive supply rail voltage that is provided to the LV PMOS input module via a high voltage ground (HV_GND) line,
• wherein at least part of the LV PMOS input module is powered by a voltage difference between the positive supply rail and the HV_GND line, and
• wherein the voltage regulator maintains said voltage difference within an operating range of one or more LV devices within the LV PMOS input module.