Differential amplifier comprising an unlocking device

An integrated circuit differential amplifier comprising:

• a first stage comprising
• first and second transistors of a first polarity connected together in a differential amplifier configuration,
• first and second current mirror sources for supplying current to said first and second transistors, respectively, and
• a control circuit having a first input receiving a reference voltage and a second input receiving a representative common mode voltage from outputs of the differential amplifier;
• a second Miller stage comprising third and fourth transistors of a second polarity receiving output signals from said first stage;
• a cascade stage connected between said first stage and second Miller stage;
• and
• an unlocking circuit connected between the representative common mode voltage and inputs of said second Miller stage for causing a short-circuit to ensure conduction of said third and fourth transistors for initiating start-up of the differential amplifier circuit.