An electrical/magnetic current sensing system includes a first collection mechanism configured to convert an electric field into surface charge, a second collection mechanism comprising a magnetic reactive material, and a sensor coupled to the first and second collection mechanisms. The sensor comprises an odd number, greater than or equal to three, of unidirectionally-coupled non-linear over-damped bi-stable elements. Each element comprises a resistive load, an operational transconductance amplifier (OTA) with a bipolar junction transistor differential pair, a cross-coupled OTA, and a non-linear OTA. Each element may comprise fully differential inputs and outputs. The sensor may be contained in a microchip or on a printed circuit board. A resident time difference readout device may be connected to the sensor, and may be configured to perform a power spectral density calculation. The sensor may include a resistance to voltage circuit connected between the second collection mechanism and the elements.