This is a simple, easy built and low cost circuit diagram of 3W stereo audio amplifier based power IC BA5406, a good general purpose stereo audio amplifier which can be used on it’s own or incorporated into existing equipment.
This power amplifier works on a simple 5-15Vdc supply. Designed with components for either 28dB (standard) or 46dB (high) gain output. The standard gain option is ideal for general audio applications and will be suitable with most pre-amps or PC sound cards, etc.
The BA5406 contains two sets of AF power amplifiers. It delivers 5W x 2 into 3 ohm loads with a 12V supply. It has minimal power-on pop noise and has immunity to supply voltage drop. It also has minimal RF radiation. Recommended supply voltage: 5-15V max, typical 12V. Quiescent current 20-70mA, typically 40mA.
Components List:
Resistors:
R1, R2 = 120R (120 Ohms)
R3, R4 = 2R2 (2.2 Ohms)
Capacitors:
C1, C2, C11, C12 = 0.22 uF (220 nF)
C3, C4, C5, C6, C7, C8 = 47 uF/16V (elco)
C9, C10 = 470 uF/16V (elco)
IC1 = BA5406
Audio Amplifier Specifications:
| Power Supply | 5 – 15Vdc |
| Current consumption | 1 – 2 Amps |
| Output | 3 Watts RMS/channel (4 Ohms, 12Vdc supply) 2 Watts RMS/channel (8 Ohms, 12Vdc supply) 2 Watts RMS/channel (4 Ohms, 9Vdc supply) |
| Output impedance | 4 – 8 Ohms |
| S/N ratio | > 85 dB, G=28 dB > 68 dB, G = 46dB |
| THD | < 0.5% @ 1W |
| Freq. response | 40 Hz to 100 kHz -3 dB (G = 28 dB, 8 ohm load) 50 Hz to 25 kHz, G=46dB |
| Gain | 28dB standard gain or 46dB high gain (see Product Documentation link below for details) |
| Input level | < 200 mV, for full output (G = 28dB) 20 mV, G = 46 dB |
| Input Impedance | ~ 100K ohm |
