New Current Drive Amplifier 02

For the voltage-type amplifier shown, if the RL load is an ideal resistor, its output current is also strictly proportional to the input
voltage , and the normalized curves can completely overlap, and it can also be regarded as having no "error" or "error" "No distortion",
if the load is not an ideal resistor, but a complex load with resistance, capacitance, inductance and back electromotive force,
its impedance changes with frequency, and the frequency component of the music signal changes with time , the output current of the voltage-type power amplifier
will change with the load and deviate from the proportional relationship with the input voltage, thus producing "error" and "distortion". Therefore,
even if the voltage-type power amplifier reaches the ideal zero-distortion state, it will not Only for the output voltage,
distortion will inevitably occur for complex output currents. Figure 6-21(b) is a schematic diagram of the current mode power amplifier. For an ideal amplifier A, its output
current is only determined by the input voltage and R determines - VL/R, and has nothing to do with the load RL, so regardless of the load size,
the output current of the current-mode power amplifier is constant and has a strict proportional relationship with the input voltage, while the output voltage is related to the load impedance.
In fact, the current-voltage relationship between current-mode power amplifiers and voltage-type power amplifiers is exactly "swap". The output current of an ideal current-mode power amplifier is zero distortion, but for complex resistive-capacitive inductive loads, its output voltage will inevitably produce distortion. We The problem faced is very simple and clear: would we rather have current without distortion or voltage without distortion? Because the speaker is a current-driven load, and the position of its diaphragm is determined by the current flowing through the voice coil, so we would rather have current without distortion. q