POWER AMPLIFIER, W-CDMA POWER AMPLIFIER, MULTIBAND POWER AMPLIFIER AND PORTABLE INFORMATION TERMINAL

摘要

PROBLEM TO BE SOLVED: To provide means capable of reducing bias currents in accordance with output power and reducing current consumption even on output conditions other than maximum output power by reconciling as variable gain means continuous bias current control and discrete gain variation.SOLUTION: An internal-temperature-compensated current control circuit 105 generates a bias current to initial stage amplifiers 102-1, 102-2 of a linear power amplifier. The current value output by the internal-temperature-compensated current control circuit 105 is determined by a setting circuit 106. The setting circuit 106 has two temperature compensation characteristics depending on an amplification factor of back stage amplifiers 103-1, 103-2 expected in the linear power amplifier and an internal temperature of the linear power amplifier.