BC548 is a commonly used NPN transistor, the same as BC547. The collector and emitter will remain open when the base pin is held at ground and will close when a signal is provided to the base pin. BC548 has a gain value of 110 to 800; this value determines the amplification capacity of the transistor. The maximum 500mA current can flow through the collector pin, so we cannot connect loads more than 500mA with this transistor. The maximum base current capacity is 5 mA.
The BC548 transistor comes in four different module numbers: BC548, BC548A, BC548B, and BC548C. The difference among the four is only their DC current gain value. The BC548 current gain value is from 110 to 800, BC548A is from 110 to 220, BC548B is from 200 to 450, and BC548C is from 420 to 800.
Technical specifications of transistor:
- Bipolar NPN Transistor
- Maximum Collector Current: 500 mA
- Max Collector-Emitter Voltage: 30V
- Maximum Collector-Base Voltage: 30V
- Max Emitter-Base Voltage: 5V
- Transition Frequency: 150 MHz
- Max Collector Dissipation: 625 MW
- Min & Max DC Current Gain: 110–800
- Max Storage & Operating temperature Should Be: -55 to +150°C
- Package Type: TO-92
Replacement and Equivalent:
BC547, 2N2222, BC549, BC550, 2N2222, BC549, and 3906 are the alternates of BC548, but the pin configuration may differ, so you must check the pin configuration before the use of any alternate of BC548.
Parameters of BC548 A, B, and C Variants
| Parameter | BC548A | BC548B | BC548C |
|---|---|---|---|
| Package of all variants | TO-92 | TO-92 | TO-92 |
| DC Current Gain (hFE) | 110-220 | 200-450 | 420-800 |
| Collector–Emitter Voltage (VCEO) | 30 V | 30 V | 30 V |
| Collector–Base Voltage (VCBO) | 30 V | 30 V | 30 V |
| Emitter–Base Voltage (VEBO) | 6.0 V | 6.0 V | 6.0 V |
| Max Collector Current (IC) | 100 mA | 100 mA | 100 mA |
| Transition Frequency (fT) | 150 MHz | 150 MHz | 150 MHz |
BC548 Transistor as a Switch Circuit
Transistors are mostly used for switching and for amplification. The circuit diagram given below shows the switching by using the BC 548 transistor.
PNP Complementary
The PNP complements of BC548 are BC556, BC557, and BC558.
Applications
- Driver modules like relay drivers, LED drivers, and switching modules.
- Amplifier modules like Audio amplifiers, signal amplifiers, etc.
- Darlington pairs can be made with this also.
- Sensor Circuits
How to Safely Long Run in a Circuit:
To increase the performance of this transistor, you should follow the guidelines and specifications given above in technical specifications. Do not drive the device above 30V, and always use the pins with the correct direction because wrong input can damage the transistor. Do not use the device in over-temperature more than 150°C.