| 摘要 |
In one band gap reference cell, first and second transistors have the bases thereof coupled together. A first supply voltage line is operatively connected to the collectors of the transistors and a second supply voltage line is operatively connected to the emitters of the transistors. The voltage supply lines produce a current proportional to temperature when the device is operating. A first resistor is connected between the emitter of one of the transistors and the second supply line. A third transistor has the base thereof coupled to the bases of the first and second transistors. A current is established in a curve-compensation resistor which is equal to the sum of the currents in the first and second transistors less a nonlinear portion which arises from variations in VBE with respect to temperature. A second resistor is connected across the base-emitter junction of one of the transistors. A current complementary to temperature is established in the resistor when the device is operating. The currents in the transistors and in the resistor are combined to produce a reference current having a predetermined temperature coefficient characteristic. Appropriate selection of resistor values enables providing a reference voltage greater than the band gap voltage.
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