Patent ID: 7616074
Filing Date: 2009-11-10
Classification: H03B,H03L

Abstract:
1. A circuit for controlling a startup time of an oscillator circuit, comprising: a variable current source coupled to the oscillator circuit, wherein a startup time of the oscillator circuit is proportional to a bias current input into the oscillator circuit from the variable current source; and a control mechanism coupled to the variable current source and to the output of the oscillator circuit, wherein upon startup the control mechanism is configured to adjust the variable current source to input a large startup bias current into the oscillator circuit; and an oscillation-detection mechanism in the control mechanism, wherein the oscillation-detection mechanism includes: wherein the control mechanism adjusts the variable current source to one or more bias currents between the large startup bias current and the steady-state bias current when a predetermined number of oscillations corresponding to each of the one or more bias currents have occurred during startup.