Voice Amplifier

Circuit Diagram
Components Required
  1. ICs
    1. IC1 TBA810
  2. Resistors
    1. R1 (100 ohms)
    2. R2 (2.2 ohms)
    3. R3 (56 ohms)
    4. R4 (100 Kilo ohms)
    5. R5 Volume Controller (1M)
  3. Capacitors
    1. C1 (1000 uF /16V)
    2. C2 (1000 uF /16V)
    3. C3 (470 uF /16V)
    4. C4 (220 uF /16V)
    5. C5 (220 uF /16V)
    6. C6 (220 uF /16V)
    7. C7 (0.01 uF)
    8. C8 (0.047 uF)
    9. C9 (1.5K )
    10. C10 (5.6 K)
    11. C11 (100 uF /16V)
  4. Others
    1. Speaker (LS 8 ohms)
    2. power supply ( 12V DC, 750mA)
    3. Flexible wires
    4. PCB or breadboard
    5. Soldering rod etc..
Principle and Working

This is a very simple and low cost audio amplifier. Small modification in this circuit can be done to use along with walkman and intercom etc.

TBA810 is heart of the circuit, which is a very powerful audio amplifier. Because of its easy availability and low cost, this IC can be seen in many gadgets. TBA810 has 12 pins, out of which pin-1 and pin-4 are are connected to positive supply, pin-9 and pin-10 are grounded. Pin-8 is used as input, and pin-12 as output. The amplified signal from pin-12 is given to Loud-speaker(LS) through capacitor(C1). The strength of the amplified signal can be controlled by controlling the intensity of the input signal. Input signal strength is controlled by the potentiometer R5 (volume control).