Voltage level detector for power amplifier protection control

A voltage level detector for protection control of a power amplifier comprising:

• an output block including a power transistor and an output terminal connected to a load;
• a bias block including a standby pin and being allowed to bias other blocks of the power amplifier in activated states, especially the power transistor conductive, when the standby pin stays active;
• a Area-of-Safe-Operation monitoring block for detecting the operation of the power transistor outside their Area of Safe Operation and issuing a cutoff signal;
• a first fault detection block for detecting fault conditions of the power transistor and the output terminal and issuing the cutoff signal;
• and
• a protection switch block for cutting off the output block from the bias block and connecting the first fault detection block to the bias block during reception of the cutoff signal;
• said voltage level detector comprising:
• a second fault detection block for monitoring the voltage level at the standby pin during power-up, and upon detection of the voltage level reaching a threshold level, detecting fault conditions of the power transistor and the output terminal;
• and
• a cutoff signal generating block for issuing the cutoff signal when the second fault detection block detects a fault condition of one of the power transistor and the output terminal.