Electrically controllable oscillator circuit, and electrically controllable filter arrangement comprising said circuits

Bram Nauta (Inventor)

    Research output: Patent

    22 Downloads (Pure)


    An electrically controllable oscillator circuit (30) comprises two balanced transconductance circuits (G1, G2), each including transistor pairs arranged as inverters (Inv14) and as resistors (Inv5-6). The oscillation frequency (f) and the quality factor (Q) of the oscillator circuit (30) are controlled by means of a single control signal provided by a combined control circuit (Inv7, Dif, IM1, IM2). The current mirror circuit (IM1, IM2) and a differential pair (Dif) derived the control signal for adjusting the quality factor (Q) from a resistor-connected further transistor pair (Inv7) connected to the control signal for adjusting the frequency (f). The quality factor of an electrically controllable filter arangement including similar transconductance circuits (G-3-9) is adjusted by means of the control signal generated by the control circuit via a buffer circuit (B) and a low-pass circuit (C3).
    Original languageUndefined
    Patent numberUS005117205A
    Priority date1/05/90
    Publication statusPublished - 26 May 1992


    • IR-102653
    • EWI-27526

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