FGMOS Based Built-In Current Sensor for Low Supply Voltage Analog and Mixed-Signal Circuits Testing

A simple current mirror using floating-gate MOS transistors (FGMOS) operating in the linear region is used in this work, to design a built-in current sensor (BICS). The important feature in this application is that the voltage drop across the sensing device can be reduced to almost zero value (less than 50 mV). This makes the proposed BICS appropriate for modern very low supply voltage applications. The proposed BICS in conjunction with an RMS-to-DC converter and a novel current window comparator can be used to efficiently achieve supply current monitoring of analog and mixed-signal circuit testing.