High-Performance Audio Power Amplifier with a Push-Pull Voltage Amplification Stage and Active Loads in the Input Differential Pair
DOI:
https://doi.org/10.5433/1679-0375.2025.v46.51473Keywords:
power amplifier, symmetrical, complementary, push-pull, active loadsAbstract
The paper proposes an innovative way to connect a differential stage with a current mirror as its load to a voltage amplification stage (VAS) without using gain-limiting resistors, employing a "buffer-bias" stage to stabilize the VAS current and preserve circuit performance. The effectiveness of the proposed topology was demonstrated through measurements on a functional prototype, which exhibited high amplifier performance, such as a total harmonic distortion of 0.0008% at 1 kHz even at full power (50WRMS) and a slew rate of 107.4V/μs.
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Copyright (c) 2025 Alexandre Saciotto Levorato, Carlos Alberto de Francisco
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