Voltage generator, a method of generating a voltage and a power-up reset circuit

摘要

A voltage generator is provided which is reliable, self starting and only requires a few components. The voltage generator comprises a first stage that provides a current to a second stage. The first stage has a temperature coefficient of one sign, such as positive, and the second stage has an opposing temperature coefficient, e.g. negative. The responses are summed such that the overall temperature coefficient is reduced.

主权项

1. A voltage generator comprising:
first and second coupled stages, wherein the first stage has a voltage versus temperature characteristic which is opposite to a voltage versus temperature characteristic of the second stage, wherein the first stage comprises:
a first transistor having a gate, a drain and a source, the first transistor configured to pass a current when its gate voltage is approximately the same as its source voltage, anda first resistive element having a first node and a second node, the first node being connected to the source of the first transistor and the second node being connected to the gate of the first transistor; wherein the second stage comprises an enhancement mode transistor, and wherein a node at which the first stage is coupled to the second stage is configured to provide a temperature compensated voltage due at least partly to a temperature coefficient of the first transistor and a temperature coefficient of the enhancement mode transistor.