| 摘要 |
A bandgap voltage reference circuit (50, 100) which operates at low power supply voltages provides a reference current as either a one- or a two- DELTA VBE voltage across a first resistor (82, 133). A current proportional to the reference current is mirrored into one terminal of a second resistor (94, 133) to provide the bandgap voltage. Compensation for base currents injected into the circuit (50, 100) by two transistors forming the DELTA VBE reference is provided. In one embodiment (50), base currents of first (66) and second (87) transistors which have equal emitter areas and collector current density as the two transistors (68, 85) forming the DELTA VBE reference compensate for the injected base currents. In another embodiment (100), a single transistor (127) injects current substantially equal to the sum of the base currents of the two transistors (116, 121) forming the DELTA VBE reference. The single transistor (127) has twice the emitter area of one of the transistors (116) forming the DELTA VBE reference.
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