I bought a voice module. During debugging, I found that the speaker has noise. When connecting the oscilloscope to watch the speaker, the 5V power supply has noise. Should it be a power supply problem? It is the power supplied by the DC power supply. May I ask how can I filter out such a situation where the voltage is pulled down?
Drake Veröffentlicht am July 15, 2020
Try to slightly modify the high-frequency filter capacitor of the power supply.
Malik Veröffentlicht am July 15, 2020
To strengthen the power supply filtering, especially the high-frequency capacitance value, the speaker will consume power, and the voltage provided by the power supply module cannot be pulled down. Normally, there should be no voltage drop.
Ellis Veröffentlicht am July 15, 2020
The current consumed by the speaker is quite large, sometimes much larger than the working current of the IC;
Adjust the voltage value properly to see if it is possible, that is, the PSSR value of the LDO is not enough, and changing the LDO will improve;
More enlarged electrolytic capacitors will also be improved;
