2N5172 Transistor Pinout, Equivalent, Features, Applications and More
2N5172 is a small signal NPN transistor available in TO-92 package. It is a general purpose transistor means you can use it in wide variety of applications. In this post we will understand 2N5172 transistor pinout, equivalents, features, application and other details.
Understanding the 2N5172 Transistor:
2N5172 is a small signal NPN BJT transistor hence it contains three pins and three layers of semiconductors which are N-type/P-type/N-type, each pin is connected with a semiconductor layers inside the transistor. The Emitter pin is connected with the N-type region that is heavily doped which means that in this layer there are large number of ready to flow electrons. The P-type layer is the thin middle layer of the transistor and the Base pin is connected with this layer this layer controls the flow of electrons from the Emitter to the Collector. The Collector pin is connected with another N-type layer but this layer has a different purpose, it is a lightly doped layer and collect electrons from Emitter N-type layer through the Base layer.
The collector-emitter voltage of the transistor is 25V it means you can drive loads under 25V, the collector current is 500mA which means you can drive load under 500mA using this transistor. The operating and storage temperature of the transistor is -55°C to +150°C below these limits can damage the transistor. The DC current gain of the transistor is from 100 to 500 which makes it ideal to use in audio preamplifier and other related applications.
Pin Configuration:
The pin configuration of the transistor are as follows:
Pin1 is the Emitter pin: The Emitter pin of the NPN transistor is connected to the ground.
Pin2 is the Collector pin: The current first enters through the Collector and through the Base it goes to the Emitter.
Pin3 is the Base pin: The load connected with the transistor is controller through the Base.
Key Features of the Transistor:
- Package Type: TO-92
- Transistor Type: NPN
- Max Collector Current(IC): 500mA
- Max Collector-Emitter Voltage (VCEO): 25V
- Max Collector-Base Voltage (VCBO): 25V
- Max Emitter-Base Voltage (VEBO): 5V
- Max Power Dissipation (PD): 625mW
- Minimum DC Current Gain (hFE): 100 to 500
- Max Storage & Operating temperature: -55 to +150 Centigrade
Replacement & Equivalent
MPSW01A, MPS6602G, MPS6601, 2SD779, FPC828, FPC945, 2SC2320L, 2SC4016, SK3899, 2SC3068, BC337, 2SD778, KTC3200.
Advantages & Disadvantages of Using 2N5172:
Here we are pointing advantages and disadvantages of choosing 2N5172 for your circuit or applications.
Advantages:
Designed for General Purpose Usage: The transistor is designed for general purpose applications which means it can be used in wide variety of applications whether it’s an amplifier, switching or other applications.
Good Small Signal Gain: The hfe of 100 to 750 makes this transistor effective in amplifying small signals.
Low Saturation Voltage: The VCE(sat) is only 0.25V maximum, this saves from energy loss.
Up to 500mA Collector Current: With 500mA of collector current capability it can drive variety of loads such as LEDs, relays, small motors.
Minimum Ccb Only 1.6pF: The high frequency performance is good due to the low collector base capacitance which reduces the signal distortion.
Good DC Current Gain: The DC current gain is from hFE 100 to 500 which make it ideal to be used in both
Disadvantages:
Low Voltage: The maximum VCEO is only 25V and VCBO is also 25V which is relatively low voltage due to which we cannot use it in high voltage applications.
Cannot be Used in High Current Applications: The collector current of 500mA is good for small low current loads but not suitable for loads for than 500mA.
Low Power Dissipation: The power dissipation is only 625mW which is not suitable for power applications and we cannot connect heatsink with TO-92 package transistors.
Not Suitable for High Speed Switching: Details about its switching speed is not mentioned in the datasheet so we cannot use it in high speed switching circuits.
2N5172 Applications:
Battery Operated Applications
LED Driver Circuits
Microcontrollers Outputs to Drive Loads
Audio Amplifier Circuits
General Purpose Switching
Preamplifier Circuits
Relay Driver Circuits
Sensor Circuits
Many other General Purpose Applications
Conclusion:
2N5172 is a good TO-92 package small signal NPN transistor designed to be used in general purpose applications. The transistor can drive load of upto 25V and 500mA and has good small signal gain of 100 to 750. It has low saturation voltage, minimum Ccb of only 1.6pF and DC current gain of 100 to 500. So you can use it for many applications such as LED & relay drivers, audio ampflifiers, switching, sensor circuits etc.
But on the other hand there are also some limitations such as the VCEO and VCBO voltage is only 25V, cannot be used for high current applications, the power dissipation is only 625mW and the switching speed of the transistor is not mentioned so you cannot use it in high speed switching applications. But if you need a transistor to drive LEDs, relays, or want make a simple amplifier or switching circuit etc. then 2N5172 is an ideal choice.
Datasheet:
To download the datasheet just copy and paste the below link in your browser.
https://www.alldatasheet.com/datasheet-pdf/view/50029/FAIRCHILD/2N5172.html
