A dual-channel CMOS transimpedance amplifier array with automatic gain control for unmanned vehicle LADARs

In this paper, a dual-channel feed-forward transimpedance(TIA) array is realized in a standard 0.18-μm CMOS technology which exploits automatic gain control function to provide 40-dB input dynamic range for either detecting targets nearby or sensing imminent danger situations. Compared to the previously reported conventional feed-forward TIA, the proposed automatic-gain-control feed-forward TIA(AFF-TIA) extends the input dynamic range 25 dB wider by employing a 4-level automatic gain control circuit. Measured results demonstrate the linearly varying transimpedance gain of 47 to 72 dBΩ, input dynamic range of 1:100, the bandwidth of ≧670 MHz, the equivalent input referred noise current spectral density of 6.9 pA/VHZ, the maximum sensitivity of - 26.8 dBm for 10^-12 BER, and the power consumption of 27.6 mW from a single 1.8-V supply. The dual-channel chip occupies the area of 1.0 × 0.73 mm² including I/O pads.