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US 6,630,865 B2Granted
Push-pull amplifiers
AssigneeTechstream Pty Ltd.
InventorsGraeme John Huon, Walter Melville Dower
Life of this patent
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AssigneeTechstream Pty Ltd.
InventorsGraeme John Huon, Walter Melville Dower
Estimating the term…
A push pull amplifier is disclosed having upper and lower output devices operating in a mode in which the devices drive a load alternately. The amplifier includes bias means for providing a bias current to the output devices at all times. The bias means is incorporated in a feedback loop and is arranged such that transitions from load current to minimum bias current in the upper and lower output devices are sufficiently gradual so that harmonic frequencies generated by the transitions are within the capability of the amplifier under all signal conditions. The feedback loop includes a non-linear transform circuit for each upper and lower output device to prevent the bias current reducing to zero. The feedback loop also includes a linearity control circuit for controlling the harmonic frequencies in the upper and lower output devices.
A push pull amplifier having output devices operating in a mode in which said devices drive a load alternately, said amplifier including bias means for providing a bias current to said devices at all times, said bias means being incorporated in a feedback loop and being arranged such that transitions from load current to minimum bias current in said upper and lower output devices are sufficiently gradual so that harmonic frequencies generated by said transitions are within the capability of said amplifier under all signal conditions, said feedback loop including non-linear transform means for each said upper and lower output device to prevent said bias current reducing to zero and linearity control means for controlling the harmonic frequencies in said upper and lower output devices.
Dependencies are inferred from the claim text.