| 摘要 |
To reduce circuit area and power consumption and suppress transient response occurring at switching in PGA of a programmable gain amplifier is provided a wireless communication receiver comprising PGAs for adjusting the gain of a received signal down-converted by mixers and sending it to base-band block. Within PGAs are provided HPFATT circuits formed of capacitors arranged in series, and ladder resistors arranged in parallel, with signal lines, and a plurality of switches. HPFATT is a circuit serving as a high-pass filter and an attenuator for gain switching, wherein switches are controlled by control signal sg from a controller. Amplifiers connected to the rear stage of the HPFATT circuit are formed of MOS transistors. |
