Patent ID: 6963250
Filing Date: 2005-11-08
Classification: H03K,H03L

Abstract:
1. A voltage controlled oscillator (VCO) having a VCO output signal with selectable frequency ranges comprising: M inverting circuits coupled in series forming M+1 nodes N( M voltage controlled feedforward inverting (VCFF) circuits, each VCFF(J) having a control voltage input, a signal input I(J) coupled to a corresponding node N(J), where J is a number (1 to M), and a signal output X(J), the first number (M−2K) of the signal outputs X( first circuitry for selectively coupling a first feedback signal selected from signals on K of first candidate nodes (N(M+1) to N(M−2K+3)), to node N( second circuitry for selectively coupling a second feedback signal from signals on K second candidate outputs X(M−1) to X(M−2K+1) to node N( third circuitry for selectively coupling a third feedback signal from signals on K third candidate outputs X(M) to X(M−2K+2) to node N(