October 25, 2022
The mobile phone motherboard circuit diagram includes the schematic diagram and bitmaps.
The motherboad bitmaps is used to analyze the circuit, find the fault detection point, and infer the fault location. It not only shows the position number of the component, but also marks the direction of the positioning pin of the circuit, which is closely related to maintenance.
The motherboad schematic diagram is to let the user know the function of each component and its circuit connection.
Each component has a unique number in the component location map of the motherboard. This number is composed of English letters and numbers. Numbering sequences can be divided into the following categories:
Chip class: start with "U", such as CPU U0201
Interface class: start with "J", such as touch interface J2401
Triode class: start with "Q", such as triode Q1101
Diodes: start with "D", such as diode D1501
Crystal type: start with "Y", such as 24M crystal Y0201
Resistors: start with "R", such as resistor R0303
Capacitors: start with "C", such as capacitor C1417
Inductors: start with "L", such as inductor L1503
Battery type: start with "B", such as backup battery B201
Screw column: start with "BS", such as screw column BS2502
Another part of the label is the test point on the motherboard, starting with "TP".
You can find the schematic diagram according to the corresponding component number to understand the function of this component. Take the iPhone6S motherboard as an example. If you want to know the main function of a certain component.
Step 1: First, find the number of the component on the bitmap. Open the iPhone6S bitmap, and find the component number U3500 according to the bitmap.
Step 2: Double click, you can jump to the component position by the component number.
There are two ways to determine the function of this component:
(1) Judging according to the line identification around the component, as shown in the figure above, it is marked with AUDIO CODEC, which indicates that the role of this chip is responsible for audio signal processing.
(2) It can be judged according to the description in the lower right corner of the drawing where the component is located.
How to Find Resistor Capacitor Components?
If you want to find a certain capacitor or resistor, and there are so many resistors and capacitors on a motherboard, is there a good way to find it? In fact, it is very simple. You only need to find the component number of the chip that is the same as the first digit of the capacitance or resistance element number, then the capacitance or resistance element is mostly around the chip. For example: want to find the location of R3030 and C3031. R3030.
C3031 and U3030 have the same first digit, so just look for U3030 in the component bitmap first, and then look around it.
November 17, 2022 0 Comments