Circuit for generating a temperature-stabilized reference voltage

Claim 1

A monolithic integrated circuit for producing an output voltage V R , comprising: first and second matched bipolar junction transistors each having a base, collector and emitter; means for coupling the emitters of the first and second transistors so that their potentials are substantially equal; means for providing a bias to the base of the first transistor to establish the base-emitter junction current density of the first transistor at a constant first value to provide a base-emitter junction voltage value V be1 having a negative temperature coefficient; a feedback circuit responsive to the emitter current of the second transistor for biasing the base of the second transistor to maintain a base-emitter junction current density of the second transistor at a constant second value to provide a base-emitter junction voltage value V be2 having a negative temperature coefficient; a resistor coupled between the bases of the first and second transistors so as to develop across the resistor a voltage substantially equal to V be2 -V be1 , the value V be2 -V be1 having a positive temperature coefficient; and resistance means in the feedback circuit series coupled with the base-emitter junction of the second transistor, the sum of the voltage across the resistance means and the base-emitter junction of the second transistor comprising the output voltage V R having the value K 1 (V be2 -V be1 )+K 2 V be2 , where K 1 and K 2 are factors determined to provide the voltage V R equal to K 2 V go , where V go is the semiconductor band gap voltage extrapolated to absolute zero, whereby the voltage V R is substantially independent of variations in temperature.