A circuit for generating a reference voltage of bandgap type. The circuit includes a current mirror assembly of cascode type including, from a high supply rail, at least two parallel branches of P-channel MOS transistors. The circuit also includes a bipolar assembly in series with one of the branches of the mirror assembly down to a low supply rail, formed of two parallel branches each including, in series, a diode-connected bipolar transistor and, respectively, one resistor and two resistors. The circuit also includes a differential amplifier for balancing the currents in the two branches of the bipolar assembly, the reference voltage being provided by the terminal of interconnection of the mirror assembly with the bipolar assembly.