Apparatus and method for transmission and remote sensing of signals from integrated circuit devices

A method of remotely detecting and establishing the value of currents in circuits in an integrated semiconductor device comprising the steps of:

• selecting an integrated semiconductor device;
• applying a voltage to a first selected circuit in said device to establish a first quiescent current in a selected portion of said first selected circuit;
• sensing said first quiescent current in said selected portion of said first selected circuit,
• converting said sensed first quiescent current in said first selected circuit to a first Hall voltage with a first magnetic field concentrator and a first Hall sensor, amplifying said first Hall voltage;
• modulating said amplified first Hall voltage with a first known frequency,
• converting said amplified and modulated first Hall voltage with a second magnetic field concentrator to create a first magnetic field pulsing at said known first frequency;
• and
• detecting said pulsating first magnetic field with a first remote sensor to provide an output signal proportional to said first sensed current.

A semiconductor testing apparatus comprising:

• means for holding a semiconductor device to be tested;
• means for applying an electrical signal to the semiconductor device to be tested to induce in said device a current through a selected path in said device
• means for establishing a current in a selected current path in said circuit;
• means for establishing a focused magnetic field at a selected position in said current path;
• means for converting said focused magnetic field into a Hall voltage;
• means for transmitting said Hall voltage to a second gated amplifier;
• means for gating said amplifier with a selected signal with a selected frequency;
• to modulate, in the amplifier, the converted Hall voltage to provide, at the output of said amplifier, a current pulsating at the frequency of said selected signal;
• means for transmitting said pulsating current pulses through a current path to establish in said current path a focused magnetic field pulsing at the frequency of said signal;
• and,
• remote magnetic sensing means for detecting said pulsating magnetic field and for providing a electrical output proportional to the current in said path.