The microphone acquires ambient sound, converts signals to electrical signals to generate analogue
signals, which are processed by the CODEC of the H603 module. Then, audio frequency is output to the
DSP for processing, and then the acquired signals are amplified by a power amplifier. The interface is a
difference interface composed of AU_VIN0_N and AU_VIN0_P signals, for reduced interference of noise.
For the both signals, static is avoided using a TVS (transient voltage suppressor) or ESD (electrostatic
discharge) component.
3.4.5 Key Circuit
Matrix keys are used. The chip AW9523B judges whether a key is pressed by scanning the level at the
GPIO port. The level is processed by the AW9523B, converted into data, and sent to the H603 module for
command execution.
To Next Page
Loading...
