Transmission power control circuit

A transmission power control circuit comprising:

• a variable gain amplifier (1) for amplifying a transmission signal with a gain according to a control voltage (VC) to output a transmitting wave;
• a plurality of distributing sections (2a to 2c) for taking out a part of said transmitting wave;
• a plurality of detecting sections (3a to 3c) provided corresponding to said respective plurality of distributing sections, respectively, and having different measurable power ranges,
• said plurality of detecting sections detecting outputs of the corresponding distributing sections to generate a plurality of detection voltages (VDET1 to VDET3) according to a transmission power (POUT) of said transmitting wave;
• and
• a control section (150a, 150b, 150c, 160a, 160b, 160c) for receiving an electrical signal indicating a designated level (PCMD) of said transmission power and said plurality of detection voltages to set said control voltage, wherein
• said control section includes a feedback ratio control section (8, 152, 157, 162, 167) setting a plurality of feedback ratios (K1 to K3) corresponding to said plurality of detection voltages, respectively, according to a relationship between the measurable power ranges of said plurality of detecting sections and said transmission power, and
• said control section sets said control voltage according to close loop control based on the plurality of detection voltages negative-fed back multiplying said plurality of feedback ratios, respectively, and a reference voltage (VREF) corresponding to the designated level of said transmission power.