Radio Frequency Integrated Circuit Design - Webs

Figure 8.20 Circuit for oscillator simulations.
Voltage-Controlled Oscillators
Figure 8.21 Plot of oscillator performance versus tank resistor: (a) open-loop and closedloop
frequency; and (b) loop gain and oscillation amplitude.
So how does one decide on the oscillator small-signal loop gain? In a
typical RF integrated oscillator, a typical starting point is to choose a smallsignal
loop (voltage) gain of about 1.4 to 2 (or 3 to 6 dB); then the current is
swept to determine the minimum phase noise. Alternatively, one might design
for optimal output power; however, typically, output buffers are used to obtain
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