Bias circuit and power amplifier circuit

A power amplifier circuit comprising:

• a bias circuit configured to generate a base bias signal;
• and
• an amplifier circuit configured to receive the base bias signal and an operation voltage, amplify an input signal, and output the amplified signal,
• wherein the bias circuit comprises:
• a first bias circuit configured to receive a reference voltage and an operation voltage and generate a first bias signal;
• a bias supply circuit configured to transmit the base bias signal to a base of a power amplifier, based on the first bias signal input from the first bias circuit;
• a switching control circuit configured to transmit a switching signal after a preset delay time based on a driving start signal;
• and
• a switching circuit connected between an output node of the first bias circuit and a ground, configured to operate in an ON state after the delay time in response to the switching signal to form a current path between the output node of the first bias circuit and the ground.

A power amplifier circuit comprising:

• an amplifier circuit;
• and
• a bias circuit configured to generate a base bias signal and transmit the base bias signal to a base of an amplifier transistor of the amplifier circuit;
• wherein the bias circuit comprises:
• a switching circuit, and
• a switching control circuit configured to receive a driving start signal and transmit a switching signal having an active voltage level to the switching circuit after a preset delay time.