1. SUB; ANALOG ELECTRONICS PREPARED BY MR.HUTESH BAVISKAR

2. TYPE OF CALSS A POWER AMPLIFIER There are two types in class A power amplifier 1) series fed class A power amplifier 2) class A power amplifier with transformer coupled load. Sub: EDC -2Topic: Class A Power Amplilfier

3. SERIES FED CALSS A POWER AMPLIFIER Sub: EDC -2Topic: Class A Power Amplilfier

5. In circuit of series fed class A amplifier fixed bias is used with the help of resistance RB connected between + VCC supply and base. Load resistance is RC. Q is an NPN type power transistor used with heat sink. Input signal vs is coupled to the base through coupling capacitor cc. Here a source vs is shown but in practice the signal comes from the previous voltage amplifier stage. Sub: EDC -2Topic: Class A Power Amplilfier

6. When no signal is applied certain base current IB flows due to the fixed bias. So certain collector current ICQ flows so some VCEQ voltage is available. The value of the base resistance is selected such that the Q point is at the middle of the active region. When the input signal is applied the base current and so the collector current changes and the operating point shifts on the load line from Q to Q1 to Q to Q2 and back to Q. Sub: EDC -2Topic: Class A Power Amplilfier

7. OPERATION OF CLASS A POWER AMPLIFIER Sub: EDC -2Topic: Class A Power Amplilfier

9. THANK YOU Sub: EDC -2Topic: Class A Power Amplilfier