In this work we have presented two novel solutions for integrated CMOS-based auto balancing bridge wide-range resistive sensor interfaces which overcome the reduced operative range of the traditional Wheatstone bridge. With respect to previous topologies based on discrete devices, here the proposed solutions have been designed in a standard CMOS technology so to be cost effective since the entire system can be integrated inside the same chip. Simulation results have confirmed the theoretical expectations and, in particular, the sensor resistance can be easily and accurately determined. Furthermore, through the use of two MOS transistors as Voltage Controlled Resistors, the estimation range has been further enlarged still maintaining a reduced estimation percentage relative error.