A low noise front end trans-impedance amplifier channel for a pulsed time-of-flight laser radar

A low noise front end trans-impedance amplifier for a pulsed time-of-flight laser range finder receiver is presented. The architecture is based on unipolar-to-bipolar pulse shaping immediately at the input of the receiver channel, where the received unipolar current pulse is converted to a bipolar current to be fed to the trans-impedance amplifier (TIA). An extensively wide dynamic range is achieved using the proposed pulse shaping scheme and TIA realization. As the timing point is located at the first zero crossing point of the bipolar signal, the non-idealities of the TIA have little effect on it. Simulations show the walk error of the TIA channel to be less than ±40ps in the dynamic range 1:100000. The input-referred noise current and bandwidth are 72nA and 415MHz, respectively.