Current-to-voltage converters often need to have a wide dynamic range and a high sensitivity. We propose a method to design such converters. The conversion is made to comprise a nonlinear compression applied to the DC component of the input current and a high gain conversion to the signal one. It is performed by a low-pass current filter and current-dependent resistances. The current filter is used to extract the DC current from the input. This DC current is then converted, with a compression, into a voltage biasing the devices that make the signal conversion. In this way, the circuit bias and the conversion of the small signal are made input-current-adaptive. A CMOS converter has been designed with this method. The simulation results show that is able to operate over a dynamic range of 4 decades.