你好! 我在用tlv320aic3101这款芯片,想通过旁路直接把输入 MIC2R/LINE2R连接到差分输出HPLOUT及HPLCOM,给芯片1k的正弦波,500mv,但是HPLCOM输出的信号频率是1k的,但是波形(附件一)不对,如果把正弦波幅度降到240,则输出是一个完整的正弦波;HPLOUT的输出有一个2.v的偏置,不波形正弦波的下半部分的一部分。请问我的思路是否正确,pga因该怎么配置?
一下是我的reg配置
aic3x_write(codec, 0x08, 0xc0);//master
aic3x_write(codec, 0x12, 0xf0); //18 right adc gain control MIC2R/LINE2R is connected to right-ADC PGA.
aic3x_write(codec, 0x16, 0x7c);//LINE1R is not connected to the right-ADC PGA. Right-ADC channel is powered up.
aic3x_write(codec, 0x10, 0x00);//The right ADC PGA is not muted. gain=0db
aic3x_write(codec, 0x18, 0x78);//LINE1L is not connected to the right-ADC PGA.
//aic3x_write(codec, 91, 0x80); //91
aic3x_write(codec, 0x38, 0x80); //56PGA_R is routed to HPLCOM.
aic3x_write(codec, 0x33, 0x09);//HPLOUT is not muted. HPLOUT is fully powered up.
aic3x_write(codec, 0x31, 0x80); //49
aic3x_write(codec, 0x3a, 0x09); //58 hplcom enalbe
主时钟12mhz,采样率8k,都没与问题