BC639 transistor
BC639 transistor electrical specification
- BC639 is a general-purpose NPN power transistor device
- Collector to emitter voltage is 80V
- Collector to base voltage is 80V
- Emitter to base voltage is 5V
- Collector current is 1A
- Power dissipation is 800mW
- DC current gain is 40 to 160hFE
- Current gain-bandwidth transition frequency (FT) is 200MHz
- Output capacitance (Cob) is 7pf
- Junction temperature is between -55 to 150℃
- Thermal resistance, junction to ambient is 200℃/W
- Collector to emitter saturation voltage (VCE (SAT)) is5V
- High current transistor device
BC639 transistor Pinout
| Pin Number | Pin Name | Description |
| 1 | Emitter | Current flows through the emitter terminal |
| 2 | Collector | Base terminal is the trigger for the transistor |
| 3 | Base | Current flow through the collector |
BC639 transistor package
The BC639 transistor had a TO-92 general-purpose transistor package, it is the most common transistor package used at low power devices.
The TO-92 package is made of epoxy/plastic material, this is because these materials had high heat resistance properties and less weight.
The shape and less weight of the BC639 transistor will help the component to make the most compact and tiny circuit network.
BC639 transistor electrical specification description/application
In this section, we try to explain the electrical specifications of the BC639 transistor device.
These descriptions are really helpful for a better understanding of the component and we can use these pieces of information for the replacement process.
Voltage specs
The terminal voltage specs of BC639 transistor are collector to emitter voltage and collector to base voltage is 80V and emitter to base voltage is 5V, these are the voltage specifications.
The collector to emitter saturation voltage is 0.5V, it is the voltage value lesser than the base voltage.
The overall voltage specs of the BC639 transistor show that it is a general-purpose transistor device mainly used for low power applications.
Current specs
The collector current value of the BC639 transistor is 1A, it is the maximum load capacity of this transistor device.
The current values of the transistor show that the BC639 transistor is much more capable of driver applications.
Dissipation specs
The power dissipation of the BC639 transistor is 800mW, the dissipation capacity of this device is mainly due to the component package.
Current gain specs
The current gain value of the BC639 transistor is 40 to 160hFE, the current gain value shows the amplification capacity of the device.
This is why the BC639 transistor had many low power amplifier applications.
Transition frequency
The bandwidth transition frequency value of the BC639 transistor is 200MHz, it is the frequency range of the transistor.
Junction temperature
With the junction temperature of -55 to 150℃, the heat capacity of the transistor is mainly dependent on the case.
The TO-92 transistor package had a moderate range of temperature capability.
Thermal resistance
The thermal resistance of junction to ambient value is 200℃/W
Input capacitance
The input capacitance value of the BC639 transistor is 50pF
BC639 transistor DATASHEET
If you need the datasheet in pdf please click this link
BC639 transistor equivalent
The transistor devices such as BC547, BC548, BC488, 2N5551, BC537, 2N5550, 2N4401, and BC337 are the equivalent transistors of the BC639 component.
The electrical specifications of these transistors are the same as BC639, so we replace these transistors in the circuits.
But we need to check and verify the PINOUT details of transistors before the replacement process.
BC639 complementary pair
The BC640 PNP is the complementary pair of the BC639 NPN transistor, the electrical specifications of each transistor are the same.
BC639 vs BC547 vs BC537
In the table, we list and compare the electrical specifications of each transistor such as BC639, BC547, and BC537.
This comparison is really helpful for a better understanding and it is really helpful for the replacement process.
| Characteristics | BC639 | BC547 | BC537 |
|---|---|---|---|
| Collector to base voltage (VCB) | 80V | 50V | 60V |
| Collector to emitter voltage (VCE) | 80V | 45V | 60V |
| Emitter to base voltage (VEB) | 5V | 6V | 6V |
| Collector to emitter saturation voltage (VCE (SAT)) | 0.5V | 90mV to 600mV | 0.7 to 1.5V |
| Collector current (IC) | 1A | 100mA | 1A |
| Power dissipation | 800mW | 500mW | 625mW |
| Junction temperature (TJ) | -55 to +150°C | -65 to +150°C | -55 to +150°C |
| Transition frequency (FT) | 200MHz | 300MHz | 100MHz |
| Gain (hFE) | 40 to 160hFE | 110 to 800hFE | 40 to 400hFE |
| Input capacitance | 50pF | 9pF | 15pF |
| Package | TO-92 | TO-92 | TO-92 |
The terminal voltage of the three transistors is the same and the BC639 & BC547 transistors had the lowest saturation voltage.
The current values of BC639 and BC537 transistors are higher than the BC547 transistor.
The BC547 transistor had many possibilities for amplification and general-purpose applications.
BC639 transistor applications
- General-purpose switching applications
- Microphone pre amp circuits
- Lighting system applications
- Relay driver
- Audio amplifier
- Signal amplifier circuits
- Radiofrequency circuits
- Darlington pair network
- Sensor circuits
Characteristics curves of BC639 transistor
The figure shows the DC current gain characteristics of the BC639 transistor, the graph plotted with DC current gain vs collector current.
At a fixed collector to emitter voltage, the DC current gain value increases from the least value with respect to collector current.
In the end, the DC current gain characteristics of the BC639 transistor form an inverted parabolic shape.
The figure shows the active region safe operating area characteristics of BC639 transistor, the graph is plotted with collector current vs collector to emitter voltage.
