A delay cell has selectable numbers of parallel load resistance transistors operable in parallel, and a similarly selectable number of bias current transistors connectable in parallel. The delay cell is preferably differential in construction and operation. A voltage controlled oscillator ("VCO") includes...http://www.google.de/patents/US6771105?utm_source=gb-gplus-sharePatent US6771105 - Voltage controlled oscillator programmable delay cells
