A Comprehensive Introduction to MJE2955T Transistor
20 October 2023
Ⅰ. Overview of MJE2955T transistor
Ⅱ. Symbol, footprint and pin configuration of MJE2955T transistor
Ⅲ. Technical parameters of MJE2955T transistor
Ⅳ. Features of MJE2955T transistor
Ⅴ. Working principle of MJE2955T transistor
Ⅵ. Absolute maximum ratings of MJE2955T transistor
Ⅶ. Dimensions and package of MJE2955T transistor
Ⅷ. Applications of MJE2955T transistor
Ⅸ. Application guide for MJE2955T transistor
MJE3055T is a silicon epitaxial-based NPN transistor in TO-220 package. The maximum collector-emitter voltage of this transistor is 60V, and the maximum emitter-base voltage is 5V. Additionally, the minimum operating temperature of this transistor is -55°C and the maximum operating temperature is 150°C. To ensure that the tansistor is not damaged during storage and transportation, it is packed in tubes. This type of packaging provides more protection by storing loose parts in the outer tube.
Since the MJE2955T is an NPN transistor, it has higher collector dissipation power and collector current and can operate at higher voltages and frequencies. In this circuit, it can input a weak signal from the base, then use the amplification function of the triode to amplify it, and finally output the amplified signal to the collector or emitter. It is commonly used in areas such as switching, video, audio and amplifiers.
Replacement and equivalent:
• 2N6491
• BD910
• KSE2955T
• MJE2955TTU
1. Pin names and description of MJE2955T
Pin 1 (Base): It works as a tap and controls the volts of the device.
Pin 2 (Collector): Electrons released by the emitter go to the collector.
Pin 3 (Emitter): Electrons transmitted from this part go to PN junction.
2. MJE2955T pin judgement
To begin, locate the front side of the triode, which can be identified by markings or its smooth surface. Subsequently, identify the three pins on this front side, typically arranged in a triangular pattern. In most cases, the central pin, slightly smaller than the other two, serves as the base. The pins flanking the base are designated as the collector and emitter, with the collector pin being slightly larger in size than the emitter pin.
• It uses lead-free packaging, which can effectively reduce environmental pollution.
• The MJE2955T transistor has good thermal and mechanical stability, allowing it to withstand large temperatures and mechanical stress in various audio equipment.
• It can work stably at higher frequencies, so it is particularly suitable for amplification of high-frequency audio signals. The high-frequency response enables it to fully ensure the quality and clarity of audio signals, presenting a more realistic sound quality effect.
• The MJE2955T transistor can provide large output power, so it can effectively drive audio equipment and amplify audio signals.
• The amplification principle of the MJE2955T transistor is to adjust the distribution of electrons in the medium to achieve the purpose of signal amplification. This method can effectively reduce the nonlinear distortion of the video signal and effectively improve the fidelity and restoration of the sound.
• It is easily integrated with other electronic components to form a complete audio amplifier or other audio circuit.
MJE2955T is a transistor made of N-type semiconductor material. When we apply a forward voltage to the emitter relative to the base, it causes the P-type semiconductor material side of the P-N junction to become thinner. At this time, electrons will flow from the P-type region to the N-type region, and holes will be formed in the P-type region. These electrons flow through the PNP junction between the base and emitter, while holes flow from the base to the emitter. At this time, the current inside the transistor is formed by the flow of electrons and holes.
As shown in the figure, the collector-to-emitter voltage of the MJE2955T transistor is 60V, while the collector-to-base voltage is slightly higher at 70V. In terms of current, the transistor can handle a significant 10A, and its collector power dissipation is rated at 75W, highlighting its ability to manage substantial power loads. The MJE2955T's robust performance and 10A collector current make it well-suited for applications demanding high load capacity. Additionally, a 6A base current is the critical threshold for initiating the transistor's operation, underscoring its triggering mechanism and the transistor's suitability for power-intensive electronic circuits and devices.
Measuring 10.4 mm in length, 4.6 mm in width, and 9.15 mm in height, the MJE2955T transistor is compact and robust for efficient integration into circuits. Additionally, the transistor comes in a TO-220 package, ensuring its safety and ease of use.
*Note: Transistor Outline Package(TO-220) is a direct plug-in package commonly used in high-power transistors and small and medium-sized integrated circuits. The size is approximately 10mm×15mm×4.5mm. It usually consists of three pins, two of which are used to connect the circuit and one for heat dissipation. Usually, TO-220 is a single-row straight plug, which can generally lead to 3, 5 or 7 pins. Common TO-220 packages include TO-220, TO-220AB, TO-220AC, TO-220D and TO-220F, etc.
TO-220 full-package (i.e. plastic-sealed) and half-packed (i.e. iron-sealed) products can meet the use needs of high-power diodes, transistors, MOS tubes and small-scale ICs. It features a heat sink design that adds heat dissipation channels to help balance the thermal characteristics of the circuit. Full-package products can achieve insulation between the heat sink and external electrical appliances, while half-package products have better heat dissipation effects. The choice of two shapes can meet the different requirements of flexible circuit design and usage conditions.
• Speed regulator: The MJE2955T transistor can be used in speed regulators such as fan controllers or power tools.
• Switching power supply: The MJE2955T transistor is well-suited for use in switch-mode power supply circuits, where it serves as a key component for power conversion. Its primary functions include voltage stabilization and current adjustment. This versatile transistor finds applications in various fields, including switch-mode power supplies, motor drives, and relay controls, where it frequently operates in a switching mode.
• Inverter: In an inverter circuit, it can be used to convert DC power into AC power, such as in Uninterruptible Power Supply System(UPS) and solar inverters.
• Power amplifier: MJE2955T can be used as the output stage transistor of the power amplifier. Its function is to amplify the weak signals in the power circuit to provide sufficient and stable power to the load.
• Lighting control: It can be used in lighting control circuits, especially applications that require brightness control, such as dimmers.
• Voltage regulator: MJE2955T is a voltage regulator suitable for voltage stabilization circuits, helping to maintain a constant voltage level.
1. Heat dissipation
The MJE2955T transistor will generate heat during operation. In order to avoid damaging the device, we must dissipate the heat reasonably. We can install a heat sink on the triode, or use natural heat dissipation and other methods to reduce the temperature of the triode.
2. Stable power supply
MJE2955T requires stable DC power supply. If the power supply is unstable, the transistor will work abnormally, and even burn out in severe cases.
3. Frequency matching
The frequency range of MJE2955T is the audio band, so it is suitable for use in audio amplifiers. If it needs to be applied to other frequency ranges, we need to choose the corresponding triode.
4. Correct connection
The MJE2955T, being an NPN transistor, requires adherence to the prescribed wiring procedure when in use. It is of importance to avoid inadvertently reversing the connection of the base and collector, as such a mistake can lead to the transistor being irreparably damaged.
5.Input signal amplitude
The amplification factor of MJE2955T depends on the amplitude of the input signal. When the input signal's amplitude exceeds a certain threshold, there's a risk of overloading and potentially damaging the transistor. Thus, it is crucial to regulate the input signal's amplitude to prevent the generation of excessively high signals.
Frequently Asked Questions
1. What are the key characteristics of the MJE3055T transistor?
The MJE3055T is known for its high collector current, low collector-emitter saturation voltage, and relatively high power dissipation capability.
2. What is MJE3055T?
The MJE3055T is a 60V silicon NPN complementary power transistor designed for use in general purpose amplifier and switching applications.
3. What are some typical applications of the MJE3055T transistor?
Some common applications include audio amplifiers, high-power LED drivers, power supplies, and motor control circuits.
4. What is the operating temperature range of MJE3055T transistor?
The operating temperature of MJE3055T transistor ranges from -55°C to 150°C.
5. What is the use of MJE3055T transistor?
The MJE3055T is a silicon Epitaxial-Base NPN transistor in Jedec TO-220 package. It is intended for power switching circuits and general-purpose amplifiers.
