Low voltage circuit design techniques for voltage controlled oscillator

This paper discusses some high frequency circuit design techniques for low voltage operation and low power consumption voltage controlled oscillators. The target operating voltage is 2 V (power supplied by only two pieces of rechargeable NiCd battery). Various resonators and circuit configurations were studied for optimal performance. A major difficulty was found in achieving high spectral purity on such low supply voltage. The presented investigation introduces efficient ways to the design of low voltage VCO for sufficient output power, low phase noise and also wide tuning range. With the simplicity and high performance, the proposed design ideas would be attractive for applications to low voltage portable products