Table data of high power transistors

Table data of high power transistors below, provide information about the type of (BD131, BD132, BD139, BD140, BD437, BD438, BD679, BD680, 2N3055, MJ2955, TIP31, TIP32, TIP33, TIP34, TIP35, TIP36, TIP41, TIP42, TIP2955, and TIP3055), type (PNP or NPN), supply voltage, current, and maximum power, HFE, HFE bias, the opponent (if the PNP type replaced with NPN type, or reverse), and packaged transistor (click here to view the package).

High power transistors or large signal transistors used for general purpose, amplifier circuit, the output power circuit, or a large current circuit switch.

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Table data of low power transistors

Table data of low power transistors below, provide information about the type of (BC107, BC108, BC109, BC140, BC141, BC160, BC161, BC177, BC178, BC179, BC327, BC328, BC337, BC338, BC546, BC547, BC548, BC556, BC557, BC558, BC639, and BC640), type (PNP or NPN), supply voltage, current, and maximum power, HFE, HFE bias, the opponent (if the PNP type replaced with NPN type, or reverse), and packaged transistor (click here to view the package).

Low power transistors or small signal transistors used for general purpose, small-signal amplifier, or the circuit switch.

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Transistors package - TO (Transistor Outline)

Packaged transistors are varied, low power transistor package will be different with the packaging of high power transistor. Low-power transistors made with the packaging from plastic or metal. Low power transistor packaging made of plastic material having a characteristic surface is flat, while those made of metal having a protrusion (tag) on the plate underneath.

Transistors with a higher power, usually made of plastic packaging, metal, or a mixture of plastic and metal. Metals in the body transistor, generally signifies a collector terminal, and specialized in high power transistor, the metal tag is useful for attaching a heat sink or appliance exhaust heat dissipation that occurs during the process.

Packaging features are intended to identify the terminal legs of the transistor. Most of the packaged transistor is grouped with the term TO (Transistor Outline).

Picture below is a transistor package which we use in the electronics world, including TO-92a, TO-92B, TO92C, TO-126, TO-220, TO-18, TO-39, TO-3, and TO-3P (N), following the legs or the terminal base, emitter, and collector.

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Key switch and DPDT switch

Key switch
Key switch is a type of switch that can only be turned on and turned off by using a key. Only a key partner and the right locking device which can be used to operate the switch. Key switch can be used in applications that require high levels of security, such as electrical control circuit in the industry.

Examples of key switch as shown in the picture below


DPDT switch
Toggle switch, rocker switch, and slide switch, can also be made ​​in a Double Pole Double Throw version, which is abbreviated with DPDT switch. Form of this switch combine two separate switches in one unit, but they operated together.

DPDT switch can be used to connect two circuits at the same time. These switches can also be connected to the neutral wire line and the line wire voltage of the source at once. When a switch is in off state, the electrical equipment connected to the switch is totally isolated from the source voltage.

Symbol of DPDT switch as shown in the picture below

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Rocker switch and Slide switch

Rocker switch
Rocker switch works the same way as a toggle switch, where there is a lever that can be pressed up and down. Lever of the rocker switches are usually called to rocker lever, shaped like an electric bell button.

Generally there are two numbers on the rocker lever, numbers 1 and 0. When the lever is pressed on number 1, indicating that the switch in the On position, and when the lever is pressed on number 0, indicating a switch in the Off position.

Examples of rocker switch as shown below


Slide switch
Slide switches are used for similar purposes to the use of toggle switches, but the slide switch is operated by using a sliding knob.

Examples of slide switches as shown in the picture below

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Rotary switch

Rotary switch is a switch type which is operated by way of played. These switches are used to connect one line to one other line, among several lines that already exist. Often, several pieces of rotary switch is used in the same unit.

Examples of common use rotary switch is serves to select a range of measurements on an AVO meter or a multimeter, or to choose a power supply voltage. This type of switch has one or more contacts are surrounded by a ring with 12 stationary contacts. Such switches are made with the composition different contacts. These arrangements can be either 1 pole of 12 lines, 2 poles 6 lines, 3 poles 4 lines or 4 poles 3 lines.

The symbol of rotary switch with 2 poles 6 lines shown bellow

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Press switch, PTM switch and PTB switch

Press switch is a type of switch that is operated by pressing a button. There are two types of press switch, ie push to make (PTM) switch and push to break (PTB) switch.

Most of the press switch is a kind of the PTM switch. By pressing a button PTM switch, the contacts will be depressed until the switch is closed and touch each other. While by pressing a button switch type of PTB switch, the contacts are normally closed contact, but will be forced open when the button is pressed.

Each type of PTM switch and PTB switch, can work to connect or disconnect during a moment or locking (latching). A switch work during a moment, will close (connect) or open (disconnect) as long as the button is pressed. When the button is released the switch will return to its original position.

Connection on the switch that locks, the button will remain in a depressed position after the first time pressed. Switch contacts will remain closed or open, depending on the type of switch is concerned. You must press the button again to unlock and return the buttons to its normal position.

Press switches are widely used in various industrial applications, the motor control circuit, and can also be used to connect power to the lights, radio devices, and other electrical equipment.

Symbol press switch such us PTM switch and PTB switch as shown below

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Toggle switch, SPST switch and SPDT switch

Toggle switch is the simplest form of switch, operated by a toggle lever that can be pressed up and down. According to the convention, position of the lever downwards to indicate OFF conditions or switch contacts is disconnected, and position of the lever upwards to indicate ON conditions or switch contacts are connected.

Toggle switch have two terminal tag, which indicates that switch have a contact type single pole single throw or single pole single direction, which is usually referred to as SPST switch.

Toggle switch that are smaller have three terminals tag, which indicates that switch have a contact type single pole double throw or single pole two direction, normally abbreviated with the SPDT switch. Terminal tag at the center is the line common current flow and can establish contact with either of these two other tag. Such contacts are called changeover contacts switch.

Symbol for SPST switch and SPDT switch as shown below

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The Switch, On condition and Off condition

The switch is a device used to control the flow of electrical current into the circuit. In the previous discussion about electric current, the electrical current will only flow in a closed circuit. So as to create a current to flow or not, we can use the switch.

Current flows when the switch contacts touch each other. In this state, the switch is said to be closed or made ​​contact.

Current can not flow into the circuit when the contacts are not touching. In this state the switch is said to be opened or lost contact.

Other terms of the condition of the switch is On and Off. On condition occurs when the contacts is made​​, and the Off condition occurs when the contact is lost.


There are various types of switches are used for many different purposes. Figure above shows the general symbols of switch, Off the conditions shown in Figure A, and On conditions are shown in Figure B.

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