MAX 10 Plus User
Manual
51
May 31, 2019
5.4
ADC/MIC/LED Demonstration
There is a high-sensitive microphone on the MAX 10 Plus board to receive the surrounding sound.
After the sound is collected and amplified approximately 392 times, as shown in
, it is
feed into the ADC of MAX 10 device. The digitized waveform will be displayed on the LED.
Meanwhile the signal will be sent to the Line-out via audio codec and DAC SMA OUT connector.
Both of which can be connected to an external speaker. The data will also be processed based on the
volume to be displayed on the 10 LEDs onboard.
Figure 5-8 Onboard Microphone Amplifier with Gain (R24/R25) = 392
◼
Function Block Diagram
is the function block diagram of this demonstration. The built-in MIC is amplified
approximately 392 times via two operational amplifiers. The signal is then feed into the ADC of
MAX 10 device for conversion. This demonstration uses the timing from the audio codec
((TLV320AIC3254) via I2S protocol to sync the entire system. The module SPI_CTL sets the
registers for the audio codec. The module SOUND_SUM syncs the digitized signal coming out of
the ADC of the MAX 10 device with the system and converts the data format i.e. adjust unsign
12-bit to sign 16-bit etc. The module DAC16 converts the digitized signal in parallel to 16-bit serial
format for the DAC chip (DAC8551) to the Line-out via audio codec (TLV320AIC3254). The
module LED_METER displays the volume of the sound on the 8 LEDs onboard.