How to Identify Component Symbols on Nokia Schematic Diagram?

[JannatLui]

Identifying with Symbols on Schematic Diagram is very easy task, it's just like reading ABC's on English alphabet.

Since we are talking about mobile phone's circuit here, we are going to tackle only on its symbols being used herein, unlike in some major electronics components which have a lot of component symbols. Mostly, because Cellphone circuits have a lot of Integrated Circuit ( IC ) meaning the circuits is being compact into a smaller circuit to produce, and save a very small space to put a huge circuit connection into one tiny piece of circuits.
I have inserted the Layout of each component and how it's look's like mounted on a PCB ( Printed Circuit Board) for better and easiest way of understanding.

Simply Click on Its Components Category for more Detailed Infos.​

Resistor

Capacitor

Transistor

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Re: How to Identify Component Symbols on Nokia Schematic Diagram?

Resistor Component's Symbol and Layout?
The symbol of a Resistor, as you can see that it is being label started with letter ''R'' meaning for Resistance and followed by a ''Mounted Code'', that code is the number of that resistor for easy identification and search reason on the whole structure of a PCB board. Then, also ob-course the Resistance Value for test and check up procedures, like for example ''R4400 = 47K'' it means that Resistor number 4400 connected on that particular circuit's value is 47K or 47000 ohms. In that way we can easily trace and and test that component using a Multi-meter tester.

There are two types shown in here, The first one is Fixed Resistor and the other one with a line across to it is called Thermistor or Thermal Resistor.

Thermistor or Thermal resistor is a variable Resistor, meaning it's resistance value is changeable. Thermal defines to heat temperature, it is being change by a current or voltage flowing across to it. It also have a capability to shut off when a voltage or current drive it to a maximum temperature level.
While the Fixed Resistor, remains steady to it's resistance value. ​

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Identifying Capacitors Symbol and Layout

There are two types of capacitors, the Polarized and the Non-polarized. The Polarized is indicated with ''+'' positive and ''-'' negative, meaning this cannot be change into its mounting position from a certain connection of a circuit polarity, The ''+'' positive is for the voltage supply line B+ only and the '' - '' negative is for the grounding lines. The capacitor will blown up if putting it into a non desired polarity position.
Non-polarized capacitor is a non-polar or without polarity meaning its position can be change without damaging it.
In Schematic Diagram it is stated as letter ''C'' stands for Capacitance then a mounting code and Capacitance value.

The Polarized indicated with desired maximum voltage value. like for example
C7597 1000mF_14V ,
the ''14V'' is the desired maximum voltage for that said capacitor.
While the Non-polarized labeled without desired voltage.
example: C2567 22pF. ​

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[JannatLui]

There are two types of standard transistors, NPN and PNP, with different circuit symbols. The letters refer to the layers of semiconductor material used to make the transistor. Most transistors used today are NPN because this is the easiest type to make from silicon.
A transistor is a semiconductor device used to amplify and switch electronic signals.
The transistor is the fundamental building block of modern electronic devices, and its presence is ubiquitous in modern electronic systems.
It is labeled with letter ''V'' and then the mounting code and product code.

The leads are labeled base (B), collector (C) and emitter (E) in some schematics while in cellphone schematics is not, just be familiar with each leads. ​

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What is a MOSFET?

Simple brief explanation, In mobile phones its is being used as a Switching circuit to the Camera Flash interface. It holds the large amount of voltage and then feed to camera flash light when it is being click to take a picture. That is why the Flash of the camera give a more bright light and speed in just a matter of blink of an naked eye..
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a device used for amplifying or switching electronic signals.
A Power MOSFET is a specific type of metal oxide semiconductor field-effect transistor (MOSFET) designed to handle large amounts of power.
Its main advantages are high commutation speed and good efficiency at low voltages.

The power MOSFET is the most widely used low-voltage (i.e. less than 200 V) switch. It can be found in most power supplies, DC to DC converters and low voltage controller circuits.
There are many types Field effect transistor, this is the one is commonly used in mobile phone circuit. ​

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