Patent ID: 8830006

Claim:
An oscillator circuit, comprising: a charge current source and a first voltage reference source; a first multiplexer with a common node, a discharge node, at least one first multiplexer control node and a charge node coupled to the charge current source, wherein in operation the first multiplexer control node controls the first multiplexer to selectively couple the common node to either the discharge node or the charge node; a second multiplexer with a shared node, a reference node, at least one second multiplexer control node and a ground node coupled to a ground rail, wherein in operation the second multiplexer control node controls the second multiplexer to selectively couple the shared node to either the reference node or the ground node; a capacitor with a first electrode coupled to the common node and a second electrode coupled to the shared node; a comparator with a first input coupled to the first electrode of the capacitor, a second input coupled to the first voltage reference source and a comparator output coupled to the first control node and the second control node; a second voltage reference source coupled to the reference node of the second multiplexer, wherein the first and second voltage reference sources provide different voltage values; a discharge current sink coupling the discharge node to the ground rail; and an oscillator output coupled to the comparator output.