Patent ID: 7528672

Claim:
An oscillator arrangement comprising: an oscillator terminal; a resonator coupled to the oscillator terminal; and a drive circuit coupled to the oscillator terminal, the drive circuit comprising: a current source circuit connected between a terminal for a first supply potential and the oscillator terminal and configured to supply the oscillator terminal with a current source current which varies periodically at an oscillator frequency and including cross-coupled first and second transistors configured to provide positive feedback in the current source circuit; and a current sink circuit connected between the oscillator terminal and a second supply potential and configured to draw a current sink current from the oscillator terminal, the current sink current varying periodically at the oscillator frequency, wherein the current sink circuit receives differential feedback signals via the current source circuit to provide negative feedback of the current sink current to the current source current such that the current sink current varies inversely to the current source current, wherein one branch of each of the differential feedback signals are low-pass filtered versions of the current source current.