A 5.7 GHz monolithic
interpolative voltage controlled oscillator using
InGaP/GaAs HBT technology is demonstrated
for the first time. Frequency tuning is achieved
by changing the open loop gain instead of the
tank capacitor. The experimental result showed
that a 400-MHz tuning range at 5.7 GHz was
realized, which can meet the requirement of
5.7GHz ISM band.
