Low-Phase Noise Hartley Differential CMOS Voltage Controlled Oscillator

Design and Investigative Aspects of RF-Low Power 0.18-µm based CMOS Differential Ring Oscillator

“…Finally by combining the eq. (3), (7), (8) and (9) one observation is obtained between oscillation frequency and the power consumption that there is a trade-off between oscillation frequency and power consumption. If the oscillation frequency increases the power consumption will also increase.…”

“…(5) and (6) will be rewritten in eq. (7) and (8). Since the mobility of electron (µ n ) is greater than the mobility of holes (µ p ) (µ p < µ n ), so in the proposed design the chosen value of (W/L) n will be greater than (W/L) p to improve the frequency range.…”

“…With the help of equation (9) another relation is obtained that power is proportional to angular frequency also. However by comparing the equation (7), (8) and (3) a relation is established that the highest frequency is achieved by using minimum load capacitance. Finally by combining the eq.…”

“…In the proposed design as shown in Figure 2, the oscillator frequency is controlled by two sources i.e., control voltages source (V cntrl ) and tail current source (V tail ). Figures 5,6,7,8 shows the effect of these two sources on the frequency of the oscillator. Actually this topology is beneficial to achieve the wide frequency range of operation of the oscillator.…”

A low power X‐band CMOS differential VCO

“…The Colpitts oscillator [2,3] can potentially achieve lower phase noise because of superior cyclostationary noise properties. CMOS Hartley VCO [4] also has high figure of merit. Despite many options available, design and optimization of an integrated LC VCO still pose many challenges to circuit designers as simultaneous optimization of multiple variables is required.…”