Patent ID: 7692481

Claim:
A band-gap reference voltage generator for low-voltage operation and high precision, comprising: first through third p-channel metal oxide semiconductor (PMOS) transistors, gates and sources of which are connected to a first node and a power supply terminal respectively, drains of which are connected to second, third and fourth nodes respectively, and which are configured as current mirrors; a feedback amplifier, which includes fourth and fifth PMOS transistors configured as current mirrors and first and second n-channel metal oxide semiconductor (NMOS) transistors, wherein non-inverting and inverting input voltages are input to gates of the first and second NMOS transistors respectively, and non-inverting and inverting output voltages are output from drains of the fourth and fifth PMOS transistors respectively; a first resistor connected to the second node and a fifth node; second, third and fourth resistors, which are connected between the second, third and fourth nodes and ground, respectively, the fourth node being a common node shared by a drain of the third PMOS transistor and one end of the fourth resistor; an output node configured to output a reference voltage, the output node being connected to the fourth node; a first bipolar transistor, which is connected with the second resistor in parallel, an emitter of which is connected to the fifth node, and a collector and a base of which are grounded; a second bipolar transistor, which is connected with the third resistor in parallel, an emitter of which is connected to the third node, and a collector and a base of which are grounded a first voltage modulator, which is connected to the gates of the first and second NMOS transistors, and crosses and modulates the non-inverting and inverting input voltages; a second voltage modulator, which is connected to the drains of the fourth and fifth PMOS transistors, and crosses and modulates the non-inverting and inverting output voltages; and a low-pass filter, which is connected between the fourth node and the ground, and passes low-frequency signals of voltage of the fourth node, wherein the first voltage modulator crosses the non-inverting and inverting input voltages to cause frequencies of the non-inverting and inverting input voltages to be modulated into odd harmonics of frequencies of the first and second clocks, and wherein the second voltage modulator crosses the non-inverting and inverting output voltages to cause frequencies of the non-inverting and inverting output voltages to be restored to the frequencies of the non-inverting and inverting input voltages.