The PAM8403 Mini Stereo Audio Amp is a miniature 3W x 2-channel stereo amplifier module that can drive 4 or 8 ohm speakers.
- PAM8403 Mini Stereo Audio Amp
KEY FEATURES OF PAM8403 MINI STEREO AUDIO AMP:
- 2-channel stereo
- 3W per channel
- Drives 4 or 8 ohm speakers
- Volume and on/off control
- 2.5 to 5.5V operation
These little stereo modules are useful if you want to add a little more sound volume to your project.
Operating voltage is 2.5 to 5.5V. The maximum power / sound output will be obtained when running the module at the higher end of its voltage range like 5V. In addition, using 4 ohm speakers will provide more sound volume than using 8 ohm speakers if you are trying to get the max volume out of these things.
The chip has good efficiencies of up to 90% and doesn’t require any heat sinking under normal use. It does have built-in thermal shutdown protection should things get too warm.
The module has an on/off and volume adjustment potentiometer which is very handy to have.
The module has 3 sets of break-out connections which include speaker outputs, power input and audio inputs. Headers can be soldered in for use with breadboards or wires can be used to make connections to these points.
1 x 4 Header Breakout (Speaker Connections)
- ROUT- = Connect to right speaker ‘-‘
- ROUT+ = Connect to right speaker ‘+’
- LOUT- = Connect to left speaker ‘-‘
- LOUT+ = Connect to left speaker ‘+’
Note: The stereo speaker outputs use 2 dedicated ‘+/-‘ wires for each speaker. Do not try to tie the two ‘-‘ lines (ROUT- and LOUT-) together or you will destroy the module.
1 x 2 Header Breakout (Power Connections)
- Power- = Ground for power supply
- Power+ = 2.5 – 5.5V power input. 5V is recommended
1 x 3 Header Breakout (Audio Input Connections)
- INPUT L = Audio input Left channel
- INPUT G = Audio ground
- INPUT R = Audio input Right channel
OUR EVALUATION RESULTS:
Sound quality is overall pretty decent and is typically better than small speakers can support. You will want to match it up with appropriate size speakers that can handle 3W if using 4 ohm speakers and 1.8W if using 8 ohm speakers or else be sure not to crank the volume all the way up to avoid damaging the speakers.
4 ohm speakers will provide the highest sound volume if that is important. 8 ohm speakers work fine but will provide about half the wattage. If using with something like our small breadboard speakers below that are rated at 0.5W / 8 ohm, it will work but you will want to go easy on the volume to avoid possible damage to the speakers.
If looking for maximum volume, then speaker efficiency / sensitivity is important, but most low cost small speakers don’t publish this spec. The spec is published in dB and the higher the dB the more sound a speaker will make for the same input. When comparing speakers, a 10dB higher efficiency for a speaker equals double the sound volume given the same input from the amplifier.
As can be seen in one of the pics, we hooked one up to our phone audio output jack and created a poor man’s boom box. The speaker ‘enclosure’ consisting of two different sizes of parts bin actually worked pretty good for a temporary setup.
The module does not ship with any headers. If you need them for your project, you can pick some up below.
BEFORE THEY ARE SHIPPED, THESE MODULES ARE:
- Sample tested per incoming shipment
|Vcc||Range (5V is typical)||2.5 – 5.5V|
|Power Output||4 ohm speakers, 5V power||3W per channel|
|THD||4 ohm speakers, 5V power||10%|
|Efficiency||up to 90%|
|Module Size||L x W x H (PCB)||29 x 20 x 13mm (1.1 x .8 x 0 .5″)|
|Mfr||Amplifier IC||Diodes Inc|