尊敬的 TI:
我的客户在测试 TLV320AIC3104时发现噪音、详情如下:
1、编解码器初始化完成后、LEFT_LOP 端口波形按如下方式进行测试、并且外部音频无噪声
2、当 CPU 播放音频并停止时、I2S 总线上没有数据传输、并且在声音中很明显可以听到"SAASA"噪声。 LEFT_LOP 端口波形按如下方式进行测试、可以看到明显的波动:
3、复位编解码器后、外部音频无噪声
编解码器寄存器值如下
# i2cdump -f -y 5 0x18
未 指定大小 (使用 字节数据 访问)
0 1 2 3 4 5 6 7 8 9 A b c d e f 0123456789abcdef
00: 00 00 00 00 10 04 00 0A 00 00 01 00 00 00 25 ……???????。。%
10: 25 0f f0 84 78 78 78 78 78 06 00 fe 00 fe 00 %?????xx????..
20: 00 00 00 cc e0 10 00 00 00 00 00 00 00 00 00 00 80 ……??…… ?
30: 00 00 00 5b 00 00 00 00 00 00 00 04 00 00 00 00 00 ?。
40: 80 5b 00 00 00 00 00 04 00 00 00 00 00 00 00 00?[... ?。
50: 00 00 80 00 00 00 5b 00 00 00 00 00 80 5b de 00 ………………………… ??[?。
60: 00 00 00 00 01 32 00 00 00 00 00 00 00 00 00 00 00 00 00 ?2..........
70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
80: 00 00 00 10 04 00 0A 00 00 01 00 00 00 25 ……???????。%
90: 25 0f f0 84 78 78 78 78 78 06 00 fe 00 fe 00 %?????xx????..
A0: 00 00 00 cc e0 10 00 00 00 00 00 00 00 00 00 00 80 ……??…… ?
B0: 00 00 5b 00 00 00 00 00 00 00 00 04 00 00 00 00 00 ?。
C0: 80 5b 00 00 00 00 00 04 00 00 00 00 00 00 00 00?[... ?。
D0: 00 00 80 00 00 00 5b 00 00 00 00 00 00 80 5b DE 00 ……………………… ??[?。
E0: 00 00 00 01 32 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ?2..........
F0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
在这种情况下、如何进一步确定噪声源并消除噪声?
谢谢!
此致!
Eric

