关于VCO buffer

lakeoffire

It depends on the specs of the VCO output buffer. For 1GHz frequency, simple inverter chains could be used as buffers, say for GSM transmitter. Generally speaking, ac couple should be used to remove the common mode output. For accurate 50 duty cycle, a correction feedback loop might be required, or you could design your VCO to work at 4GHz and divide the output by 4.