Butler type oscillator with restricted load of electromechanical resonator

摘要

In the present invention, there is disclosed an oscillator comprised of two amplification stages with a first field-effect transistor (Q1) in connection with a common gate and a second field-effect transistor (Q2) in connection with a common drain. A load impedance (Z) is connected between the first field-effect transistor (Q1) drain and a supply voltage bus (ViDD). A second resistor (R2) is connected between the second field-effect transistor (Q2) drain and the supply voltage bus (ViDD). Said first field-effect transistor (Q1) drain is connected to one end of a first capacitor (C1) having its other end connected to both the gate of the second field-effect transistor (Q2) and to the joint of a fourth resistor (R4) and a fifth resistor (R5). The other end of the fourth resistor (R4) is connected to a common conductor or a source of the second field-effect transistor (Q2). The other end of the fifth resistor (R5) is connected to the gate of the first field-effect transistor (Q1) being at the same time connected to one end of a second capacitor (C2). Said second capacitor (C2) other end is connected to the common conductor. The source of the first field-effect transistor (Q1) is connected to one end of a third resistor (R3) and to one end of an electromechanical resonator (X1) having its other end connected to the source of the second field-effect transistor (Q2) being connected to one end of the first resistor (R1). The second end of the third resistor (R3) and that one of the first resistor (R1) are connected to the common conductor. One end of the third capacitor (C3) is connected between the drain of the second field-effect transistor (Q2) and an output voltage live terminal (Viout).