| CPC G05F 3/26 (2013.01) [G05F 3/30 (2013.01)] | 11 Claims |

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1. A bandgap reference circuit, comprising:
a complimentary to absolute temperature (CTAT) current generator providing a CTAT current and including a source degeneration resistor;
a proportional to absolute temperature (PTAT) current generator providing a PTAT current and comprising:
a first branch comprising a source degeneration resistor, a first p-type metal-oxide semiconductor (PMOS) transistor, and a first n-type metal oxide semiconductor (NMOS) transistor, a resistor, and a diode-connected transistor;
a second branch comprising a source degeneration resistor, a second PMOS transistor, a second NMOS transistor, and a diode-connected transistor, the second branch coupled to the first branch in a current mirror configuration; and
a chopper circuit alternately coupling drain terminals of the first and second PMOS transistors to the remainder of their respective branches;
a first current mirror coupled to mirror the CTAT current and including a source degeneration resistor;
a second current mirror coupled to mirror the PTAT current and including a source degeneration resistor;
an output configured to combine the mirrored CTAT and PTAT currents to provide a reference current;
a first lowpass filter coupling gates of the first and second PMOS transistors of the PTAT current generator to a gate of a PMOS transistor in the second current mirror; and
a second lowpass filter coupling a gate of a PMOS transistor in the CTAT current generator to a gate of a PMOS transistor of the first current mirror.
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