Bandgap type reference voltage source with low supply voltage

摘要

Bandgap type reference voltage source using an operational transimpedance amplifier. The bandgap stage is formed by a first and a second bandgap branch parallel-connected; the first bandgap branch comprises a first diode and a transistor, series-connected and forming a first output node; the second bandgap branch comprises a second diode and a second transistor series-connected and forming a second output node. The operational amplifier has inputs connected to the output nodes of the bandgap stage. An amplifier current detecting stage is connected to the outputs of the operational amplifier and supplies a current related to the current drawn by the operational amplifier. A diode current detecting stage is connected to the output of the amplifier current detecting stage and to an output of the operational amplifier and supplies a current related to the current flowing in the first diode. An output stage transforms this current into a stabilized voltage.