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YlmzZn , 10-25-2025, 07:34 AM

I use audio transformer for **`MIC-IN`** pin **`CM108B`** IC. But, I don't know how to configure the transformer. Some designs have **`10k potentiometer`** to the between **`GND`** and **`SIGNAL LINE`** of secondary side of transformer. Is there any other configuration for this? The picture is my **`MIC-IN`** design and **`MICIN_JACK`** port will connect with audio transformer. How can I connect audio transformer to **`MICIN_JACK`** pin? and someone can explain the meaning of this microphone input design configuration (for instance, why some designs have 10k potentiometer or any other passive component?).
-# Transformer model: **__`78615/9JC`__**