摘要 |
An inductorless voltage biasing circuit is provided for an AC-coupled amplifier of the type having a signal input terminal and a coupling capacitor for coupling the input terminal to a control terminal of the AC-coupled amplifier. The voltage biasing circuit includes a voltage source coupled to the control terminal, with the voltage biasing circuit including a differential-input amplifier having a noninverting input coupled to the voltage source, an inverting input, an output terminal and a differential voltage gain characteristic that decreases as a function of frequency. A resistor is coupled between the inverting input and the output terminal, and the control terminal of the AC-coupled amplifier is coupled to the inverting input of the differential-input amplifier. In this manner, a low-impedance DC-voltage biasing source is provided for an AC-coupled amplifier without using an inductor.
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