| Abstract: | Wireless communication systems, such as WLAN or Bluetooth receivers, employ preamble data to estimate the channel characteristics, introducing stringent settling‐time constraints. This makes the use of traditional closed‐loop feedback automatic gain control (AGC) circuits impractical for these applications. In this paper, a compact feedforward AGC circuit is proposed to obtain a fast‐settling response. The AGC has been implemented in a 0.35 μm standard CMOS technology. Supplied at 1.8 V, it operates with a power consumption of 1.6 mW at frequencies as high as 100 MHz, while its gain ranges from 0 dB to 21 dB in 3 dB steps through a digital word. The settling time of the circuit is below 0.25 μs. |
