Bias voltage generating device and operating method

A bias voltage generating device, comprising:

• a reference bias circuit connected to a first voltage and a second voltage, the reference bias circuit comprising a first diode-connected transistor pair which includes a diode-connected p-type transistor and a diode-connected n-type transistor;
• a driving circuit configured to provide, at an output terminal, a third voltage based on the first voltage and the second voltage;
• a first current mirror;
• a first transistor comprising:
• a gate coupled to gates of the diode-connected p-type transistor and the diode-connected n-type transistor of the first diode-connected transistor pair, and
• first and second source/drains coupled correspondingly to a first end of the first current mirror and the output terminal;
• and
• a second current mirror coupled between a second end of the first current mirror and the output terminal.

A method, comprising:

• supplying a first voltage and a second voltage to a reference bias circuit, a sense circuit and a driving circuit, wherein
• the reference bias circuit comprises a first diode-connected transistor pair which includes a diode-connected p-type transistor and a diode-connected n-type transistor,
• the sense circuit is connected to an output terminal of the driving circuit, and comprises a first transistor, and
• gates of the diode-connected p-type transistor and the diode-connected n-type transistor of the first diode-connected transistor pair are connected to a gate of the first transistor;
• providing a third voltage at the output terminal of the driving circuit based on the first voltage and the second voltage;
• and
• in response to the sense circuit sensing a change in the third voltage at the output terminal, controlling the driving circuit to reduce the change in the third voltage at the output terminal.