Amplitude limiting method for a differential amplifier
AssigneeATMEL Germany GmbH
InventorsJuergen Eckert, Juergen Schnabel
Life of this patent
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AssigneeATMEL Germany GmbH
InventorsJuergen Eckert, Juergen Schnabel
Estimating the term…
A control unit and two negative feedback branches limit the amplitudes of the output signal of an inverting differential amplifier. Each feedback branch includes a threshold value switch including a transistor as well as an adjustable current source and a resistor forming a voltage divider between a supply voltage and the amplifier output. The voltage divider output is connected to the transistor's base. The transistor selectively connects or disconnects the input of the amplifier with either the supply voltage or the amplifier output. The control unit controls the two current sources based on external programming commands, to establish two adjustable threshold values within which the negative and positive amplitudes of the output signal are limited, symmetrically or independently, in a hard or soft clipping manner. Even with small supply voltages, the limited output will not overdrive subsequent amplifier input stages and will not superimpose harmonics on the useful signal.
An amplifier circuit including an inverting differential amplifier having an output signal with a limited amplitude, said circuit comprising:
A method of limiting the positive and negative amplitudes of an output signal of a inverting differential amplifier using a control unit, a first threshold value switch connected to said differential amplifier in a first negative feedback loop, and a second threshold value switch connected to said differential amplifier in a second negative feedback loop, said method comprising the following steps:
Dependencies are inferred from the claim text.