Bandgap device and start-up circuit thereof

A bandgap device, wherein the bandgap device comprises:

• a bandgap circuit, configured to provide a bandgap voltage;
• and
• a start-up circuit, coupled to the bandgap circuit, configured to start the bandgap circuit, wherein the start-up circuit comprises:
• a first transistor, wherein a first terminal of the first transistor is coupled to a first voltage, and a control terminal of the first transistor is controlled by a first internal bias voltage of the bandgap circuit;
• a delay circuit, wherein a first terminal of the delay circuit is coupled to a second terminal of the first transistor, and a second terminal of the delay circuit is coupled to a second voltage;
• a second transistor, wherein a first terminal of the second transistor is coupled to a third voltage, and a control terminal of the second transistor is controlled by a second internal bias voltage of the bandgap circuit;
• a switch circuit, wherein a first terminal of the switch circuit is coupled to a second terminal of the second transistor, a second terminal of the switch circuit is coupled to a fourth voltage, and a control terminal of the switch circuit is controlled by an output terminal of the delay circuit;
• and
• a first startup switch, wherein a first terminal of the first startup switch is coupled to a fifth voltage, a second terminal of the first startup switch is coupled to a first internal startup node of the bandgap circuit, and a control terminal of the first startup switch is coupled to the second terminal of the second transistor and the first terminal of the switch circuit.