COMPARISON BETWEEN VOLTAGE AND POWER AMPLIFIER







sl.no Characteristics Voltage Amplifier Power Amplifier
1 Current Gain High, exceeding 100 Low 20-50
2 Collector Load High about 10KΩ Low 5-20Ω
3 Input Voltage Low, a few mV High, 2-4V
4 Collector Current Low about 1mA High exceeding 100mA
5 Power output Low High
6 Power dissipation capacity Less than 0.5W More than 0.5W
7 Output Impedence High about 10KΩ Low about 200Ω
8 Coupling Usually RC coupling Transformer or tuned circuit



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