is then i bias instead of v cc r for a voltage supplied wheatstone bridge consequently by setting a low current value the overall power dissipation is greatly reduced the disadvantage of this type of bias is the output level of the signal this is because the output signal of the wheatstone bridge is directly proportional to the current passing through the sensitive resistors 2 and 4 therefore by reducing this current the level of the output signal 14 is reduced the invention makes it possible to solve the problems of the conditioning circuits of fig1 and 2 based on the use of a passive wheatstone bridge composed only of resistors by proposing an amplification circuit which consumes a low current while guaranteeing an acceptable output signal level and a non degraded bandwidth various embodiments of the amplification circuit according to the invention are described in the rest of the description with reference to fig3 to 10 the circuit shown in fig3 comprises a p mos field effect transistor 20 the source of which is connected to the variable resistor 2 representing the sensitive element of the resistive sensor the signal of which is to be recovered the drain of the transistor 20 is connected to a load consisting of a reference resistor r 1 denoted by the reference 22 at the terminals of which the amplified signal 14 is recovered the gate of the transistor 20.