1 Watt audio amplifier for Mobile device

About LM4890

1 Watt audio amplifier for mobile device has been designed using LM4890 power amplifier. LM4890 is primarily designed for mobile phones and other portable devices. It is capable of delivering 1 watt of continuous average power to an 8 ohm load from 5v power supply. It has a distortion of less than 1%.

LM4890 does not require output coupling capacitors and therefore ideally suited for mobile phones and other low voltage applications where minimal power consumption is primary requirement. Power output at 5v is 1 watt and at 3.3 v it is approximately 0.4 watt.

Circuit diagram

LM 4890 - 1 watt audio power amplifier

Parts required.

  • C1= 1 μf 16v
  • C2=0.39 μF 50v
  • C3=1 μf 16 v
  • C4=25 pf
  • R1, R2, R3 = 20 k
  • J1 an dJ2 = Jumper head vertical mount
  • Speaker – 8 Ω

For more circuits on audio amplifier click here

Audio Amplifier using LM386

Audio amplifier using LM386 is a power amplifier designed to be used in low voltage consumer applications. Typical applications are like portable AM/FM amplifier, TV sound systems. It requires minimum external parts and operate from wide range of voltage starting from as low as 4 volt.Below is the version of the circuit designed by me in one of my projects. It has a Gain of 50 with Bass boost.

1 Watt Audio Amplifier


1 watt audio amplifier shown below is very simple and easy to make. You can use this in making pocket amplifier for your mp3 player. It can fit in small mactch box size box.

1 Watt audio Amplifier


Parts List for making 1 watt audio amplifier

  • Q1 Transistor – MPSW45A
  • R1- 50 ohms
  • R2- 10 K
  • R3,R4 – 100 K
  • 9 volt battery and Speaker

If you need more power you can view my other post on audio amplifier using LM386