BC556 transistor
BC556 transistor electrical specification
- BC556 Bipolar junction PNP transistor
- Collector to emitter voltage is -80V
- Collector to base voltage is -80V
- Emitter to base voltage is -5V
- Collector current is –100mA
- Pulsed collector current is -200mA
- Power dissipation is 500mW
- DC current gain is 110 to 800hFE
- Transition frequency (FT) is 150MHz
- Junction temperature is between 150℃
- Collector to emitter saturation voltage (VCE (SAT)) is -90 to -650mV
- Thermal resistance is 250℃/W
- Noise figure (NF) is 2 to 10dB
BC556 transistor Pinout
| Pin Number | Pin Name | Description |
| 1 | Collector | Current flows through the collector |
| 2 | Base | The base is the trigger for the transistor |
| 3 | Emitter | Current start flows from the emitter, it is the input of the transistor |
BC556 transistor package
The transistor package used at BC556 is TO-92, it is a package mainly used for compactness and also helps to lower its overall weight.
The TO-92 transistor package is made with a mixture of epoxy and plastic material, these materials are good at heat withstanding.
BC556 transistor electrical specification description with application note
In this section, we descript the BC556 transistor electrical specification and also its applications.
Voltage specs
The voltage specs of BC556 transistor are collector to base voltage is -80V, collector to emitter voltage is -65V, and emitter to base voltage is -5V, the voltage specs show that it is a medium power transistor.
The collector to emitter saturation voltage value is -90 to -650mV, it is a lower value for saturation switching.
Current specs
The collector current value is -100mA, the current value of the transistor shows that they are capable of low load, this is why they are been used for small load switching circuits.
The pulse collector current value is -200mA.
Dissipation specs
The power dissipation value of the BC556 transistor is 500W, it is a moderate value of dissipation.
Current gain specs
The current gain value is between 110 to 800hfE, the gain value is the indication of amplification capability.
Transition frequency specs
The transition frequency value of the BC556 transistor is 150MHz, it is the frequency range of the device.
Junction temperature
The junction temperature of 150℃, which is a general-purpose transistor temperature value of capacity.
BC556 transistor DATASHEET
If you need the datasheet in pdf please click this link
BC556 transistor equivalent
The transistor devices such as BC558, S8550, A1015, BC557, 2N3906, 2SA1017, and 2N4403 are the equivalent of a BC556 transistor.
All of these transistors had the same electrical specifications as BC556, so we can use them as the equivalent.
BC556 vs BC327 vs 2SA1017
In this table, we try to compare the electrical specifications of BC556 vs BC327 vs 2SA1017, this type of comparison is really helpful to understand more about the transistor to make circuit networks.
| Characteristics | BC556 | BC327 | 2SA1017 |
|---|---|---|---|
| Collector to base voltage (VCB) | -80V | -50V | -120V |
| Collector to emitter voltage (VCE) | -65V | -45V | -100V |
| Emitter to base voltage (VEB) | -5V | -5V | -5V |
| Collector to emitter saturation voltage (VCE (SAT)) | -90 to -650mV | -0.7V | -0.5V |
| Collector current (IC) | -100mA | -800mA | -50mA |
| Power dissipation | 500mW | 625mW | 500mW |
| Junction temperature (TJ) | 150°C | 150°C | 125°C |
| Transition frequency (FT) | 150MHZ | 260MHZ | 110MHZ |
| Gain (hFE) | 110 to 800hFE | 100 to 630hFE | - |
| Package | TO-92 | TO-92 | TO-92 |
The voltage specs of these three transistors are almost the same, the 2SA1017 transistor had a higher value of collector terminal to voltage.
At the current value, the BC327 transistor had a higher value than the other two transistors.
The transition frequency value is higher for the BC327 transistor, this is why they had more audio system-based applications.
BC556 transistor Complementary
The transistor BC546 is the NPN complementary for the BC556 PNP transistor, the electrical and physical specifications of both transistors are the same, and this is why BC556 and BC546 complementary pair based circuits are been used in some applications.
BC556 transistor applications
- Switching applications
- Amplifier circuits
BC556 transistor characteristics
The figure shows the DC gain characteristics of the BC556 transistor, the graph is plotted with DC current gain vs Collector current.
At a fixed collector to emitter voltage, the DC gain starts at a point with respect to collector current, and then the gain value will drops.
The figure shows the static characteristics of the BC556 transistor, the graph is plotted with collector current vs collector to emitter voltage.
At different base current values, the collector current had different values of variations with respect to voltage variations.
