Band-gap voltage generator

摘要

A generator of a voltage logarithmically variable with temperature may include a differential amplifier having a pair of transistors, each coupled with a respective bias network adapted to bias in a conduction state the transistors first and second respectively with a constant current and with a current proportional to the working absolute temperature. The pair of transistors may generate between their control nodes the voltage logarithmically variable with temperature. The differential amplifier may have a common bias current generator coupled between the common terminal of the differential pair of transistors and a node at a reference potential, and a feedback line to provide a path for the current difference between the sum of currents flowing through the transistors of the differential pair and the common bias current.

主权项

1. A voltage generator comprising:
first and second bias networks; a differential amplifier comprising first and second transistors, each transistor being coupled respectively to said first and second bias networks and comprising a control terminal, said first and second transistors having a common terminal therebetween; said first and second bias networks configured to respectively bias in a conduction state said first and second transistors respectively with a constant current and with a proportional to absolute temperature (PTAT) current; said first and second transistors configured to generate between said control terminals a voltage logarithmically variable with temperature; a common bias current generator coupled between the common terminal and a reference potential; and a feedback path configured to provide a path for a current difference between a sum of the constant current and the PTAT current, and a current of the common bias current generator, said feedback path comprising a third transistor coupled between said common terminal and a supply reference voltage, said first transistor comprising a conduction terminal configured to control said third transistor.