Using a clock signal generated by a microcomputer for providing a negative bias voltage to a galium arsenide field effect transistor in a high frequency amplifier of the device

A mobile radio communication device including a microcomputer supplying system clock signals having a predetermined frequency and a high-frequency power amplifier having a GaAs FET, said device comprising:

• negative voltage generating means for receiving said system clock signals and forming a negative voltage;
• and
• a control circuit for selectively supplying said negative voltage supplied from said negative voltage generating means to a gate of said GaAs FET, activation and deactivation operations of said GaAs FET being controlled in accordance with said negative voltage,
• wherein said control circuit is electrically coupled between said negative voltage generating means and said gate of said GaAs FET.

An RF power module comprising:

• a first terminal for receiving a power supply voltage
• a second terminal for receiving an earth potential;
• an input terminal for receiving an input signal;
• an output terminal;
• a clock input terminal for receiving clock signals having predetermined frequency;
• a GaAs FET having a drain coupled to said output terminal and to said first terminal electrically, a source coupled to said second terminal, and a gate coupled to receive a signal based on said input signal;
• and
• a negative voltage generator electrically coupled between said clock input terminal and said gate of said GaAs FET for rectifying said clock signals on the clock input terminal and forming a negative voltage being not more than said earth potential.

A mobile telephone comprising:

• an antenna;
• a signal source unit for generating first radio signals;
• a transfer unit having a power amplifier for amplifying said first radio signals to produce amplified signals having a predetermined transmission power and for supplying said amplified signals to said antenna;
• a reception unit for receiving and modulating second radio signals from said antenna;
• a switch circuit;
• a control unit having a microprocessor which synchronously performs operations in accordance with first clock signals having a predetermined frequency, said microprocessor including means for outputting second clock signals in accordance with said first clock signals, said control unit being electrically coupled to said signal source unit, said transfer unit, said reception unit and said switch circuit for controlling said signal source unit, said transfer unit, said reception unit and said switch circuit;
• and
• a voltage generator which generates a bias voltage of a negative level in accordance with said second clock signals and which supplies said bias voltage to said power amplifier,
• wherein said switch circuit is controlled by said control unit so that said transfer unit and said reception unit are selectively coupled to said antenna.