Circuit for generating a temperature stabilized reference voltage

Claim 1

A monolithic integrated circuit for producing a temperature independent output voltage V R , comprising: first and second matched bipolar junction transistors each having a base coupled together and to a reference voltage node, a collector and an emitter; a first resistor coupled between the emitter of the first transistor and a common voltage node; second and third resistors series coupled between the reference voltage node and the common voltage node; and means for biasing the first and second transistors conductive including feedback means for providing a feedback voltage to the reference voltage node to establish respective base-emitter junction voltage values V be1 and V be2 each having a negative temperature coefficient, the feedback means including a fourth resistor coupled between the emitter of the second transistor and a node between the second and third resistors and a comparator amplifier having one input connected to the emitter of the first transistor, a second input connected to the node between the second and third resistors and an output coupled to the reference voltage node, the output of the comparator amplifier biasing the first and second transistors conductive so as to establish the voltage value V be1 across the second resistor resulting in a voltage across the fourth resistor that is equal to the value V be2 -V be1 having a positive temperature coefficient, whereby the currents through the second and third resistors establish a voltage across the fourth resistor having a value K 1 V be1 +K 2 (V be2 -V be1 ) where K 1 and K 2 are scaling factors determined by the second, third and fourth resistors, the sum of the voltages across the second and third resistors at the reference voltage node comprising the regulated output voltage V R .