Abstract: The present invention concerns a circuit (30; 50) for supplying a first current (I3) to an external element (3), this current having to be supplied with high precision at a desired nominal value. The current supply circuit includes a first transistor (T3) through which the first current flows, an operational amplifier (A2) to a first input of which a reference voltage (Vref) is supplied, and to an output of which a control signal from the first transistor is supplied, and an external resistor (Re1; Re2). These the circuit is characterized in that it further includes a second transistor (T4) through which a second current (I4; I4/m) flows, said second current also flowing through the external resistor. Such an arrangement of the circuit according to the present invention allow the value of the first current to be trimmed with great precision to its nominal value.