Regulator circuit
The present invention is contrived to adopt a differential pair type amplifier circuit comprising a differential pair constituted by a first transistor receiving an input of a first signal and by a second transistor receiving an input of a third signal generated by outputting a second signal of which the voltage level is a power supply voltage. Elements requiring a matching are two transistors constituting the differential pair for the amplifier circuit. Because of this, the elements requiring a matching can be placed close to each other regardless of a layout between the amplifier circuits.
1. A regulator circuit comprising a plurality of amplifier circuit, comprising:
a load driving amplifier for supplying a load current by generating a predetermined constant power supply voltage, a replica amplifier comprising fundamentally the same as the load driving amplifier and an operational amplifier for forming a feedback circuit in association with the replica amplifier, as the plurality of amplifier circuits,
the load driving amplifier and the replica amplifier comprises a differential pair constituted by a first transistor for receiving an input of a first signal output from the operational amplifier and by a second transistor receiving an input of a third signal generated by dividing a voltage of a second signal of the power supply voltage by a resistance voltage division circuit, and
the operational amplifier generates and outputs, the first signal according to a difference of a potential between a fourth signal used as a reference and the third signal output from the replica amplifier.
2. The regulator circuit according to claim 1 , wherein
the load driving amplifier and the replica amplifier comprise a current source for making a sum of currents supplied by said differential pair constant.
3. The regulator circuit according to claim 1 , further comprising
a charging-use amplifier for charging a capacitance element connected to said load driving amplifier for stabilizing said second signal.
4. The regulator circuit according to claim 1 , wherein
said first signal is a signal of a bandgap voltage.