| 摘要 |
A relatively precise and accurate current reference system and method are described. The present current reference system and method facilitate realization of relatively high accuracy and precision in current references independent of process, voltage and temperature (PVT) variations. In one embodiment, a current reference system includes an opamp (operational amplifier), a first transistor and second transistor, a first resistor and a second resistor of different temperature coefficients, and a third transistor and fourth transistor. The opamp indicates and corrects the potential difference between a first branch and a second branch. The first transistor and second transistor mirror currents in the first branch and the second branch. The first resistor and a second resistor of different temperature coefficients cause voltage drops across them in a manner that compensates for PTAT variations. The third transistor and fourth transistor provide voltages between respective bases and emitters.
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