| 摘要 |
A thermal voltage referenced current source has a plurality of current mirrors coupled in an unstacked manner, each powered by a power supply such that the current mirrors operate with approximately equal bias currents, and at least one reference voltage output connected to a node of one of the current mirrors. The unstacked coupling of the current mirrors allows a reference current at the reference voltage output to have a temperature coefficient of about 1000 ppm/°C. This very low temperature dependence can be achieved with power supplies having a voltage of 1.5 volts or less, and the reference current changes by less than about one percent within a wide range of operating temperatures (5 to 105° C.). A gain stage may be formed using a current source, and a pair of source-coupled transistors connected to the current source and controlled by the current mirrors. A bandgap generator can be constructed using the foregoing thermal voltage reference circuit, which has a positive temperature coefficient, in combination with a negative temperature coefficient base-to-emitter voltage (Vbe) reference circuit, or by providing a suitable choice of resistor material.
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