iPhone audio circuit repairing

This video mainly explains how to find the signals of iPhone 11 Pro, Pro Max microphone 2 and microphone 3

Microphone 2 is connected to the power connector,

and microphone 3 is connected to the earpiece connector

Search method step 1, find the power connector or the earpiece connector in the component map

Step 2, determine the position numbers of the connectors at the same position in the bitmap

Step 3, search for the position numbers in the schematic diagram

After finding the connectors, check the pin identifications of the connector

The one marked with MIC means the signal of the microphone

Step 4 Jump to the bitmap to view the connected components according to the pin identification

The voltage and diode value can be measured at the position of the yellow point in the bitmap

Let's look for the signals of microphone 2 first

When checking the maps, first open the component maps, circuit diagrams,

and bitmaps of iPhone 11 Pro and ProMax

Find the power connector in the component map,

and determine the position number of the power connector at the same position in the bitmap

Then search for the position number in the schematic diagram

After finding the power connector, the pin marked MIC means the signal of the microphone

Pins 4, 6, 8, and 10 of the connector are the signals of microphone 2

Pin 4 is the power supply for microphone 2, jump to the bitmap according to the name

The power supply pin is connected to the fuse inductor FL7705,

And connected to the large audio U4700 after the inductor

Pin 6 of the connector is the bias detection signal, jump to the bitmap

The bias detection signal is directly connected to the large audio

Pin 8 of the connector is the data positive of the microphone, jump to the bitmap

The data is connected to the fuse inductor FL7706,

and after passing through the inductor, it is connected to the large audio

Pin 10 of the connector is the data negative of microphone 2, jump to the bitmap

The data negative is connected to the fuse inductor FL7707,

and after passing through the inductor, it is connected to the large audio

Let's find the signals of microphone 3

Microphone 3 is connected to the large audio by the earpiece connector

Locate the earpiece connector in the component map

And determine the position number at the same position in the bitmap

Then search for the position number in the schematic diagram

After finding the connector, the pin marked MIC is the signal of the microphone

Pins 25, 27, and 28 of the connector are the signals of microphone 3

Pin 25 is the power supply for microphone 3, jump to the bitmap according to the name

The power supply pin is connected to the fuse inductor FL7940,

and after passing through the inductor, it is connected to the large audio

Pin 27 is the data negative of microphone 3, jump to the bitmap according to the name

The data negative is connected to the fuse inductor FL7941,

and after passing through the inductor, it is connected to the large audio

Pin 28 of the connector is the data positive, jump to the bitmap according to the name

The data is connected to the fuse inductor FL7942,

and after passing through the fuse inductor, it is connected to the large audio

In this way, we have searched for all the signals of microphone 2 and microphone 3

If the corresponding function is not normal,

it is necessary to measure the corresponding connector

If the value of the connector is abnormal,

check the components connected to the line according to the diagram to rule out damage

That's all for this video