| 摘要 |
Described embodiments provide a voltage controlled oscillator (VCO) that includes an operational amplifier (opamp). The opamp has a positive power supply input coupled to a power supply voltage, a negative power supply input coupled to a ground node, an inverting input coupled to a control voltage of the VCO, a noninverting input that receives a feedback signal, and an output providing a transistor control voltage. A transistor having a gate terminal coupled to the output of the opamp, a source terminal coupled to the power supply voltage, and a drain terminal coupled to a resistor coupled to ground, generates an output current. A current mirror generates a mirror current based on the output current. A current controlled oscillator (ICO) is coupled to the current mirror, and sets the frequency of the VCO output signal based upon the mirror current. |
