2N3773 Transistor Equivalent, Features and Applications
08 October 2023
Ⅱ. Symbol and pin connection of 2N3773
Ⅳ. What are the features of 2N3773?
Ⅴ. How does the 2N3773 achieve amplification and switching functions in the circuit?
Ⅵ. How to identify the quality of 2N3773?
Ⅶ. Absolute maximum ratings of 2N3773
Ⅷ. How to use 2N3773 transistor?
Ⅸ. What are the applications of 2N3773 in circuits?
2N3773 is a high-power audio transistor in TO-3 type package, suitable for various linear applications, such as head positioner driver. In addition to power switching circuits, such as relay or solenoid drivers, DC-DC converters or inverters, they can also be used in high-efficiency audio amplifiers. Its operating temperature range is -65°C to 200°C, its performance is stable and reliable, which ensures that the transistor can maintain excellent performance in various harsh environments. Moreover, its compact size, lightweight design, and ease of integration have made it a commonly utilized component in contemporary electronic devices.
Replacement and equivalent:
• 2N3000
• 2N3012
• 2N3772G
• 2N3773G
2N3773 is an NPN transistor. It mainly consists of three terminals: Base, Emitter and Collector. Its functions are as follows:
Pin1 (Base): Control number of electrons
Pin2 (Emitter): Emits numbers of electrons
Pin3 (Collector): Collects number of electrons
• Limited frequency response: Suitable for applications in the low to mid frequency range.
• High current and voltage: The 2N3773 has high collector current and collector-emitter voltage ratings, which enables it to handle high current and high voltage conditions, making it suitable for high power applications.
• Extreme Power: The 2N3773 is a high power transistor, typically capable of handling power levels from tens to hundreds of watts, making it ideal for use in power amplifier and power switching applications.
• Thermal Characteristics: Since the 2N3773 usually needs to handle higher power, heat dissipation is very important. It usually needs to be used in conjunction with a heat sink to ensure temperatures are kept within acceptable limits during high power operation.
1. Magnification function
When the transistor is used as an amplifier, the input signal enters from the base, and through the amplification effect of the transistor, the signal is amplified and output from the collector. In this process, the amplification factor of the triode can be adjusted through resistors and other components to meet different amplification needs.
2. Switch function
When the transistor is used as a switch, a control signal is input to the base, and the transistor is switched between saturated conduction and cut-off states by adjusting resistors, capacitors and other components. When the transistor is in a saturated conduction state, it is equivalent to a closed switch and the circuit is in a conductive state. When the transistor is in the cut-off state, it is equivalent to an open switch and the circuit is in an open state.
Step 1: Appearance Inspection
First, check the appearance of the triode. Make sure there is no obvious physical damage such as cracks, cracks, oxidation or signs of burns. If there is something wrong with the appearance, it is likely that the transistor is damaged.
Step 2: Test the Pins
We use a multimeter or multipurpose tester to measure the pins of the triode. The 2N3773 has a base, emitter and collector, labeled B, E and C. Typically, the pins are connected as follows:
The resistance between B (base) and E (emitter) should be a high value, usually above a few thousand ohms.
The resistance between B (base) and C (collector) should be a high value, usually above a few thousand ohms.
The resistance from E (emitter) to C (collector) should be a low value, usually a few hundred ohms or less.
Step 3: Test the PN junction
When we measure between base and emitter, we usually notice a specific voltage drop, which is between 0.6 and 0.7 volts. This voltage drop is a sign of the normal operation of the diode, which represents the voltage loss generated when current passes through the diode. If the measurement does not show the expected voltage drop, or if the voltage drop value is unusually high, this may mean that the diode is partially damaged.
Step 4: Test the HFE (or beta) Value
The magnification of measuring 2N3773 is usually expressed as HFE or beta value. To operate, clamp the two probes of the multimeter between the base and emitter, then connect a current limiting resistor to the collector, and then measure the current between B and E. It has been verified that the HFE value of a normally working 2N3773 is usually between 20 and 100.
Step 5: Test the Resistance From Collector to Package
This resistor should be a higher value, usually above a few hundred ohms. If this resistance value is very low, it may indicate that the transistor is damaged.
Step 6: Temperature Test
We use a thermometer or infrared thermometer to detect the temperature of the triode. A properly functioning triode should maintain a relatively stable temperature during normal operation. If a transistor becomes unusually hot with no load or low load, it may indicate a problem with it.
1. Connect correctly
When using the 2N3773 transistor, we need to connect its three electrodes correctly. Among them, the collector and emitter can be used interchangeably, but the base must be connected correctly to control the switching state and amplification factor of the triode.
2. Pay attention to the withstand voltage and current
The withstand voltage and current capacity of the 2N3773 triode are limited. When using it, you need to ensure that it does not exceed its rating to avoid damage to the triode.
3. Pay attention to heat dissipation
The transistor generates heat when working. If the temperature is too high, its performance and stability may be affected. Therefore, when using the 2N3773 triode, we need to pay attention to its heat dissipation issues and take appropriate heat dissipation measures, such as installing heat sinks or fans.
4. Connect transistors in the circuit
Depending on the application requirements, we connect the transistors into the circuit. For example, in a common emitter amplifier configuration, the collector is typically connected to the positive supply voltage, the emitter is connected to the load, and the base is connected to the input signal through an appropriate bias resistor.
5. Apply power
Once everything is properly connected, we can power the circuit and monitor its performance. Especially in high power applications we have to be careful as incorrect connections or excessive voltage or current can damage the transistor.
6. Test and adjust
In order to obtain the best performance of a circuit, it usually needs to be tested and adjusted according to the specific application needs. These adjustments may include changing the values of the bias components to help stabilize the amplification performance of the circuit.
7. Pay attention to protection
Transistors are relatively fragile components and may be damaged if they are used incorrectly or are subject to excessive current surges. Therefore, when using the 2N3773 transistor, we need to pay attention to protecting it to prevent excessive current, overcurrent, overvoltage, etc.
• Filter: The transistor can be used as a filter to filter out noise and interference signals in the circuit, improve the signal-to-noise ratio of the circuit, and thereby improve the performance of the circuit.
• Protection component: Since 2N3773 has high voltage resistance and large current capacity, it can be used as a protection component to prevent overload or short circuit. When an abnormality occurs in the circuit, the triode will automatically cut off the circuit to protect other components in the circuit from damage.
• Oscillator: Through amplification and switching, triodes can form various forms of oscillators, such as LC oscillators, RC oscillators, etc., used to generate signals of various frequencies and waveforms.
• Amplifier: 2N3773 can be used as an amplifier. It can receive a weak input signal and output a signal with greater amplitude and more power through the amplification of the triode. Usually, this application requires the use of other components such as resistors and capacitors to build a complete amplifier circuit.
• Switch: 2N3773 can also be used as a switch. By controlling the on-off state of the triode, the switch control of the circuit is realized. This application method usually needs to be used in conjunction with other components such as relays and contactors to achieve remote control of the circuit.
Frequently Asked Questions
1. What is the 2N3773 transistor?
The 2N3773 is a high-power NPN bipolar junction transistor (BJT) commonly used in power amplifiers, voltage regulators, and other high-power electronic circuits.
2. What type of transistor is the 2N3773?
The 2N3773 is an NPN (Negative-Positive-Negative) bipolar junction transistor.
3. What is a 2N3773 transistor used for?
The 2N3773 is a PowerBaset power transistor designed for high power audio, disk head positioners and other linear applications. This device can also be used in power switching circuits such as relay or solenoid drivers, DC−DC converters or inverters. Stresses exceeding Maximum Ratings may damage the device.
4. Are there any precautions to consider when using the 2N3773 transistor in high-power circuits?
Yes, when using the 2N3773 transistor in high-power circuits, it's important to provide proper heat sinking and ensure that the maximum ratings for current, voltage, and power dissipation are not exceeded to prevent overheating and potential damage to the transistor.
