Patent ID: 8531169
Filing Date: 2013-09-10
Classification: G05F,Y10S

Abstract:
1. A circuit for generating a proportional to absolute temperature (PTAT) voltage, comprising: a first bipolar transistor and a second bipolar transistor sharing a common base; a first current source supplying current to the first transistor; a second current source supplying current to the second transistor; and a resistorless active element connected between an emitter of the first transistor and an emitter of the second transistor, the active element also being connected in a feedback loop to a collector of the second transistor to generate, in accordance with a collector current density ratio of the first transistor and the second transistor, the PTAT voltage as a difference between a base-emitter voltage of the first transistor and a base-emitter voltage of the second transistor; wherein the first transistor is operated at n times a current density of the second transistor.