Floating to referenced output conversion

Claim 1

A CIRCUIT FOR SENSING AN UNREFERENCED DIFFERENTIAL OUTPUT SIGNAL FROM A DIFFERENTIAL AMPLIFIER AND CONVERTING IT TO A SIGNAL REFERENCED TO A PARTICULAR POTENTIAL COMPRISING: FIRST AND SECOND TRANSISTORS HAVING THEIR EMITTERS CONNECTED TO A COMMON SOURCE OF CURRENT AND THEIR BASES ELECTRODES ADAPTED TO BE CONNECTED TO RESPECTIVE FIRST AND SECOND INPUT SIGNALS, FIRST IMPEDANCE CONNECTING THE COLLECTOR OF ONE OF SAID FIRST AND SECOND TRANSISTORS TO A SOURCE OF POTENTIAL OF A GIVEN AMPLITUDE AND POLARITY, MEANS FOR PROVIDING A BIAS POTENTIAL OF SAID GIVEN POLARITY BUT LESS THAN SAID GIVEN AMPLITUDE BY AN AMOUNT EQUAL TO THE VOLTAGE DROP ACROSS SAID FIRST IMPEDANCE WHEN SUBSTANTIALLY ALL OF SAID SOURCE CURRENT IF FLOWING THERETHROUGH, SECOND IMPEDANCE SUBSTANTIALLY EQUAL TO SAID FIRST IMPEDANCE, SAID SECOND IMPEDANCE COUPLING THE COLLECTOR OF THE OTHER ONE OF SAID FIRST AND SECOND TRANSISTORS TO SAID BIASING MEANS, AND A THIRD TRANSISTOR HAVING ITS BASE-EMITTER CIRCUIT CONNECTED BETWEEN THE COLLECTORS OF SAID FIRST AND SECOND TRANSISTORS AND ITS COLLECTOR CONNECTED TO AN OUTPUT TERMINAL FROM WHICH A REFERENCED OUTPUT SIGNAL IS DERIVED.