Start-up circuit for bandgap reference

A reference voltage generation device comprising:

• a bandgap reference circuit having a first branch including a first transistor, a first resistor and a first diode in series, suitable for generating a first current, a second branch including a second transistor and a second diode in series, suitable for generating a second current, and an output circuit suitable for generating a bandgap voltage based on the sum of the first and second currents;
• and
• a start-up circuit suitable for starting-up the bandgap reference circuit,
• wherein the start-up circuit includes:
• a replica diode for the second diode;
• an operational amplifier including input terminal coupled to the second diode, a second input terminal coupled to the replica diode, and an output terminal;
• a first current branch including a third transistor and a fourth transistor in series between power supply terminal and a ground terminal, suitable for generating a first current in response to an output voltage at the output terminal of the operational amplifier;
• a second current branch including a fifth transistor and a sixth transistor in series between the power supply terminal and the ground terminal, suitable for generating a second current in response to the output voltage at the output terminal of the operational amplifier;
• a second resistor coupled in parallel to the sixth transistor;
• an inverter coupled to a connection node between the fifth transistor and the sixth transistor, suitable for inverting a voltage at the connection node and generating an inversion voltage;
• and
• a seventh transistor suitable for controlling the second transistor in response to the inversion voltage.