LA4440 is a dual channel audio amplifier IC. It can be used in two modes; one is Stereo amplifier and another Bridge amplifier mode. The LA4440 is a monolithic linear IC from Sanyo. Here I give the both circuit mode of amplifier using IC LA4440.
Features of IC LA4440
- It has 46dB of ripple rejection
- Low distortion
- Good channel separation
- Thermal protector
- Overvoltage protector
- Surge voltage protector
LA4440 Stereo Amplifier Circuit
When the IC LA4440 is Stereo mode in the circuit, its output power is 6w+6w. In stereo mode use two pieces speaker of 2Ωto8Ω.
In the stereo amplifier configuration given below, C11 and C12 are output capacitor. But i ignore them from the circuit of bridge amplifier.
In the stereo amplifier configuration given below, C11 and C12 are output capacitor. But i ignore them from the circuit of bridge amplifier.
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| Fig-1: LA4440 Stereo Amplifier Circuit Diagram |
LA4440 Bridge Amplifier Circuit
When the IC LA4440 is in Bridge mode in the circuit, its output power is 19w. In bridge mode use 4Ω-8Ω speaker. If you want stereo output(19w+19w) in bridge mode then use two copies of amplifier circuit of given below. Resistor R3&R4 is to adjust the voltage gain and for making input signal of inverting amplifier.
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| Fig-2: LA4440 Bridge Amplifier Circuit Diagram |
Circuit description for both, stereo and bridge amplifier mode
C10 is filter capacitor used to reduce the ripple of supply voltage. Don’t decrease the value of capacitor C6&C7 less than 100uF, 10v, it may causes of the output at low frequencies goes lower. The pin-6 of LA4440 amplifier circuit is audio input pin; it used in stereo amplifier mode but in bridge mode it is grounded. C8&C9 are polyester film capacitor used to preventing oscillation, and R1&R2 used for the same reason as filter resistor. Though the maximum supply voltage for both circuit of amplifier is 18V but we recommend to use a 12V,3A power supply. Use a good quality heat sink with LA4440.
I think here you see little comparison between stereo and bridge amplifier of LA4440. If you want to make this amplifier project, then I recommend you the bridge one. I think it is ideal for a beginner. And I love its wattage rather than Stereo mode. There is also a possibilities as I say, make two copies of circuit of bridge amplifier for stereo, it will give you 19w+19w of audio power output.
