Hello, I’m working with EG91 Evaluation Board trying to take a look into the CODEC IC to connect to a speaker and playing with the AT command for testing.
My goal is to connect SPK output to a bigger, already working, amplifier circuit for hallway voice.
I have had no results trying to make sound come out of the Loudspeaker Interface (J603) in the EVB.
I connected an osciloscope with 2 probes to each pin of J603 (SPK_P and SPK_N) and a reference to GND for each probe, afterwards I tried a few commands to make sound come out:
-Select ACL5616 CODEC IC
AT+QDAI=3,0,0,4,0,0,1,1
-Select speaker mode
AT+QAUDMOD=2
-Create a tone to sound over the speaker
AT+QLTONE=1,1000,200,300,3000
With this method the sound comes out only from the J601 headphone jack, I’ve tried all 3 modes for the “AT+QAUDMOD=” but the result is the same.
I have the following documents that helped me try this:
-Quectel_UMTS_LTE_EVB_User_Guide_V2.1
-Quectel_WCDMA_LTE_Audio_Design_Note_V1.1
-Quectel_EG91_Hardware_Design_V1.6
-Quectel_EG9x_AT_Commands_Manual_V1.1
-ALC5616 Datasheet from Realtek
-NCP2823 Datasheet from ONsemi
In the vecinity of the amplifier U801 (NCP2823) there is a connection J604 that maybe is the power source of the amplifier, I’m not sure and I can’t find anywhere what this connection is for.
Is there some step that I’m not taking?
Or maybe something I’m missing in hardware?
I don’t want to try things without certenty, EVB is very expensive and I have olny one.
