Patent ID: 7616065
Filing Date: 2009-11-10
Classification: H03L

Abstract:
1. A method of generating a correction signal for a voltage controlled oscillator (VCO) comprising: receiving a first signal in a correction current generator; changing a state of a first error signal substantially simultaneously with a first changing state of the first signal; receiving a second signal in the correction current generator; changing a state of a second error signal substantially simultaneously with a first changing state of the second signal; changing the state of the first error signal substantially simultaneously with a second changing state of the second signal; changing the state of the second error signal substantially simultaneously with a second changing state of the first signal; combining the first error signal and the second error signal to generate the correction signal substantially equal to a difference between the first error signal and the second error signal; and applying the correction signal to a loop filter coupled to a correction signal input of the VCO, wherein the correction current generator includes a selector circuit including a buffered select signal equal to an inverse of a product of a buffered first signal and a buffered second signal and an inverted select signal equal to a product of the buffered first signal and the buffered second signal, wherein the correction signal includes a single correction current output including a common mode rejection.