BC556 PNP Transistor: Pinout, Datasheet, and Equivalent
SMALL SIGNAL BIPOLAR TRANSISTOR
The BC556 is a general-purpose PNP bipolar junction transistor mainly employed in switching and AF (audio frequency) amplifier applications.

1.5V LED flasher using BC556 and BC546
BC556 Description
The BC556 is a general-purpose PNP bipolar junction transistor mainly employed in switching and AF (audio frequency) amplifier applications. The collector-emitter voltage of the BC556 is -65V therefore it can be used to drive loads up to -65V DC with a max 100mA current. With a 500mW collector dissipation (Pc) and 110 to 800 DC current gain, the BC556 can also be used in a variety of general signal amplification and audio preamplification purposes.
The BC556 is manufactured in three different part numbers, BC556A, BC556B, and BC556C. The only difference between them is their hFE values. The BC556 has a current gain between 110 and 800. The BC556A ranges from 110 to 220, BC556B ranges from 200 to 450, and BC556C ranges from 420 to 800.
BC556 Pinout

BC556 CAD Model
Symbol

Footprint

3D Model

BC556 Features
Package Type: TO-92
Transistor Type: PNP
Max Collector Current (IC): -100 mA
Max Collector-Emitter Voltage (VCE): -65 V
Max Collector-Base Voltage (VCB): -80 V
Max Emitter-Base Voltage (VBE): -5 V
Max Collector Dissipation (Pc): 500 mW
Max Transition Frequency (fT): 100 MHz
DC Current Gain (hFE): 110 to 800
Storage & Operating temperature: -65 to +150 Centigrade
Specifications
- TypeParameter
- Mounting Type
The "Mounting Type" in electronic components refers to the method used to attach or connect a component to a circuit board or other substrate, such as through-hole, surface-mount, or panel mount.
Through Hole - Package / Case
refers to the protective housing that encases an electronic component, providing mechanical support, electrical connections, and thermal management.
TO-226-3, TO-92-3 (TO-226AA) - Surface Mount
having leads that are designed to be soldered on the side of a circuit board that the body of the component is mounted on.
NO - Transistor Element Material
The "Transistor Element Material" parameter in electronic components refers to the material used to construct the transistor within the component. Transistors are semiconductor devices that amplify or switch electronic signals and are a fundamental building block in electronic circuits. The material used for the transistor element can significantly impact the performance and characteristics of the component. Common materials used for transistor elements include silicon, germanium, and gallium arsenide, each with its own unique properties and suitability for different applications. The choice of transistor element material is crucial in designing electronic components to meet specific performance requirements such as speed, power efficiency, and temperature tolerance.
SILICON - Current-Collector (Ic) (Max)100mA
- Number of Elements1
- Operating Temperature
The operating temperature is the range of ambient temperature within which a power supply, or any other electrical equipment, operate in. This ranges from a minimum operating temperature, to a peak or maximum operating temperature, outside which, the power supply may fail.
150°C TJ - Packaging
Semiconductor package is a carrier / shell used to contain and cover one or more semiconductor components or integrated circuits. The material of the shell can be metal, plastic, glass or ceramic.
Bulk - Published1996
- JESD-609 Code
The "JESD-609 Code" in electronic components refers to a standardized marking code that indicates the lead-free solder composition and finish of electronic components for compliance with environmental regulations.
e1 - Pbfree Code
The "Pbfree Code" parameter in electronic components refers to the code or marking used to indicate that the component is lead-free. Lead (Pb) is a toxic substance that has been widely used in electronic components for many years, but due to environmental concerns, there has been a shift towards lead-free alternatives. The Pbfree Code helps manufacturers and users easily identify components that do not contain lead, ensuring compliance with regulations and promoting environmentally friendly practices. It is important to pay attention to the Pbfree Code when selecting electronic components to ensure they meet the necessary requirements for lead-free applications.
yes - Part Status
Parts can have many statuses as they progress through the configuration, analysis, review, and approval stages.
Obsolete - Moisture Sensitivity Level (MSL)
Moisture Sensitivity Level (MSL) is a standardized rating that indicates the susceptibility of electronic components, particularly semiconductors, to moisture-induced damage during storage and the soldering process, defining the allowable exposure time to ambient conditions before they require special handling or baking to prevent failures
1 (Unlimited) - Number of Terminations3
- Terminal Finish
Terminal Finish refers to the surface treatment applied to the terminals or leads of electronic components to enhance their performance and longevity. It can improve solderability, corrosion resistance, and overall reliability of the connection in electronic assemblies. Common finishes include nickel, gold, and tin, each possessing distinct properties suitable for various applications. The choice of terminal finish can significantly impact the durability and effectiveness of electronic devices.
TIN SILVER COPPER - Terminal Position
In electronic components, the term "Terminal Position" refers to the physical location of the connection points on the component where external electrical connections can be made. These connection points, known as terminals, are typically used to attach wires, leads, or other components to the main body of the electronic component. The terminal position is important for ensuring proper connectivity and functionality of the component within a circuit. It is often specified in technical datasheets or component specifications to help designers and engineers understand how to properly integrate the component into their circuit designs.
BOTTOM - Peak Reflow Temperature (Cel)
Peak Reflow Temperature (Cel) is a parameter that specifies the maximum temperature at which an electronic component can be exposed during the reflow soldering process. Reflow soldering is a common method used to attach electronic components to a circuit board. The Peak Reflow Temperature is crucial because it ensures that the component is not damaged or degraded during the soldering process. Exceeding the specified Peak Reflow Temperature can lead to issues such as component failure, reduced performance, or even permanent damage to the component. It is important for manufacturers and assemblers to adhere to the recommended Peak Reflow Temperature to ensure the reliability and functionality of the electronic components.
NOT APPLICABLE - Time@Peak Reflow Temperature-Max (s)
Time@Peak Reflow Temperature-Max (s) refers to the maximum duration that an electronic component can be exposed to the peak reflow temperature during the soldering process, which is crucial for ensuring reliable solder joint formation without damaging the component.
NOT APPLICABLE - Pin Count
a count of all of the component leads (or pins)
3 - JESD-30 Code
JESD-30 Code refers to a standardized descriptive designation system established by JEDEC for semiconductor-device packages. This system provides a systematic method for generating designators that convey essential information about the package's physical characteristics, such as size and shape, which aids in component identification and selection. By using JESD-30 codes, manufacturers and engineers can ensure consistency and clarity in the specification of semiconductor packages across various applications and industries.
O-PBCY-T3 - Qualification Status
An indicator of formal certification of qualifications.
COMMERCIAL - Configuration
The parameter "Configuration" in electronic components refers to the specific arrangement or setup of the components within a circuit or system. It encompasses how individual elements are interconnected and their physical layout. Configuration can affect the functionality, performance, and efficiency of the electronic system, and may influence factors such as signal flow, impedance, and power distribution. Understanding the configuration is essential for design, troubleshooting, and optimizing electronic devices.
SINGLE - Power - Max
Power - Max is a parameter that specifies the maximum amount of power that an electronic component can handle without being damaged. It is typically measured in watts and indicates the upper limit of power that can be safely supplied to the component. Exceeding the maximum power rating can lead to overheating, malfunction, or permanent damage to the component. It is important to consider the power-max rating when designing circuits or systems to ensure proper operation and longevity of the electronic components.
500mW - Transistor Application
In the context of electronic components, the parameter "Transistor Application" refers to the specific purpose or function for which a transistor is designed and used. Transistors are semiconductor devices that can amplify or switch electronic signals and are commonly used in various electronic circuits. The application of a transistor can vary widely depending on its design and characteristics, such as whether it is intended for audio amplification, digital logic, power control, or radio frequency applications. Understanding the transistor application is important for selecting the right type of transistor for a particular circuit or system to ensure optimal performance and functionality.
SWITCHING - Polarity/Channel Type
In electronic components, the parameter "Polarity/Channel Type" refers to the characteristic that determines the direction of current flow or the type of signal that can be accommodated by the component. For components like diodes and transistors, polarity indicates the direction in which current can flow through the component, such as forward bias or reverse bias for diodes. For components like MOSFETs or JFETs, the channel type refers to whether the component is an N-channel or P-channel device, which determines the type of charge carriers that carry current through the component. Understanding the polarity or channel type of a component is crucial for proper circuit design and ensuring that the component is connected correctly to achieve the desired functionality.
PNP - Transistor Type
Transistor type refers to the classification of transistors based on their operation and construction. The two primary types are bipolar junction transistors (BJTs) and field-effect transistors (FETs). BJTs use current to control the flow of current, while FETs utilize voltage to control current flow. Each type has its own subtypes, such as NPN and PNP for BJTs, and MOSFETs and JFETs for FETs, impacting their applications and characteristics in electronic circuits.
PNP - DC Current Gain (hFE) (Min) @ Ic, Vce
The parameter "DC Current Gain (hFE) (Min) @ Ic, Vce" in electronic components refers to the minimum value of the DC current gain, denoted as hFE, under specific operating conditions of collector current (Ic) and collector-emitter voltage (Vce). The DC current gain hFE represents the ratio of the collector current to the base current in a bipolar junction transistor (BJT), indicating the amplification capability of the transistor. The minimum hFE value at a given Ic and Vce helps determine the transistor's performance and efficiency in amplifying signals within a circuit. Designers use this parameter to ensure proper transistor selection and performance in various electronic applications.
110 @ 2mA 5V - Current - Collector Cutoff (Max)
The parameter "Current - Collector Cutoff (Max)" refers to the maximum current at which a transistor or other electronic component will cease to conduct current between the collector and emitter terminals. This parameter is important in determining the maximum current that can flow through the component when it is in the cutoff state. Exceeding this maximum cutoff current can lead to malfunction or damage of the component. It is typically specified in the component's datasheet and is crucial for proper circuit design and operation.
15nA ICBO - Vce Saturation (Max) @ Ib, Ic
The parameter "Vce Saturation (Max) @ Ib, Ic" in electronic components refers to the maximum voltage drop across the collector-emitter junction when the transistor is in saturation mode. This parameter is specified at a certain base current (Ib) and collector current (Ic) levels. It indicates the minimum voltage required to keep the transistor fully conducting in saturation mode, ensuring that the transistor operates efficiently and does not enter the cutoff region. Designers use this parameter to ensure proper transistor operation and to prevent overheating or damage to the component.
650mV @ 5mA, 100mA - Voltage - Collector Emitter Breakdown (Max)
Voltage - Collector Emitter Breakdown (Max) is a parameter that specifies the maximum voltage that can be applied between the collector and emitter terminals of a transistor or other semiconductor device before it breaks down and allows excessive current to flow. This parameter is crucial for ensuring the safe and reliable operation of the component within its specified limits. Exceeding the maximum breakdown voltage can lead to permanent damage or failure of the device. Designers and engineers must carefully consider this parameter when selecting components for their circuits to prevent potential issues and ensure proper functionality.
65V - Transition Frequency
Transition Frequency in electronic components refers to the frequency at which a device can transition from one state to another, typically defining the upper limit of its operating frequency. It is a critical parameter in determining the speed and performance of active components like transistors and integrated circuits. This frequency is influenced by factors such as capacitance, resistance, and the inherent characteristics of the materials used in the component's construction. Understanding transition frequency is essential for optimizing circuit designs and ensuring reliable signal processing in various applications.
150MHz - Frequency - Transition
The parameter "Frequency - Transition" in electronic components refers to the maximum frequency at which a signal transition can occur within the component. It is a crucial specification for digital circuits as it determines the speed at which data can be processed and transmitted. A higher frequency transition allows for faster operation and better performance of the electronic component. It is typically measured in hertz (Hz) or megahertz (MHz) and is specified by the manufacturer to ensure proper functioning of the component within a given frequency range.
150MHz - RoHS Status
RoHS means “Restriction of Certain Hazardous Substances” in the “Hazardous Substances Directive” in electrical and electronic equipment.
ROHS3 Compliant
BC556 Functional Alternatives

BC556 Equivalents
2SA1016, 2SA1017, 2SA1082, 2N4403, A1015, A733, 2N2907, BC880, BC879, BC490, 2N5821, BC327
Please check pin configuration before you replace them in your circuit.
BC556 NPN Complementary
Where to use BC556
The BC556 is a general-purpose transistor mainly employed in switching and AF (audio frequency) amplifier applications. It can be used as a preamplifier or in preamplifier stages, as an audio amplifier or in audio amplifier stages, or in any other type of general signal amplification application. We can also use it as a switch to drive loads under 100mA. The 100mA collector current is quite enough to drive small loads in electronic circuits like relays, LEDs, high power transistors, etc. Moreover, with the -5V emitter-base voltage, the BC556 can also be used at the output of microcontrollers.
BC556 Applications
Preamplifier
General-purpose audio amplifier
General signal amplification
Darlington pair
Drive load under 100mA
H-Bridge circuits
Current mirror circuits
Linear amplifiers
Impedance buffering
Switching applications
Bistable multivibrators
Astable vibrator
Oscillator circuits
Comparator circuits
BC556 Package

BC556 Manufacturer
Rochester Electronics is the largest continuing source manufacturer of semiconductors in the world. With product licensing from leading manufacturers such as Analog Devices, Altera, Cypress, Fairchild, Freescale, Infineon, Intel, NXP, Renesas and Texas Instruments, Rochester continues to manufacture and distribute mature products. For industrial, transportation and hi-reliability markets, this extension of product life is critical for long term production and maintenance. With over 100,000 products and 15 billion units in stock, no other company compares to our selection, capabilities or solutions.
Trend Analysis
Datasheet PDF
- Datasheets :
1.What is BC556?
BC556 is a general-purpose transistor and is mainly employed for switching and AF (audio frequency) amplifier applications. The BC556 transistor gets on when the Base-Emitter Voltage exceeds 0.55 volts. The transfer characteristics of the transistor are defined as the relation between the input and output voltage.
2.What is the price of BC556?
Estimated unit price $ 0.2 - $ 0.3.
3.How to get long term performance of BC556 in a circuit?
To get long term performance with this transistor it is suggested to not drive load more than 100mA and -45V DC, always check pin configuration before placing in the circuit, use a suitable base resistor for the transistor and do not operate or store the transistor in temperature below -65 centigrade and above +150 centigrade.
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