2SC945 transistor specification
- 2SC945 is High frequency amplifier NPN transistor type
- Collector to emitter voltage is 40V
- Collector to base voltage is 50V
- Emitter to base voltage is 5V
- Collector current is 1A
- Base current is 20mA
- Power dissipation is 250mW
- DC current gain is 50 to 185hFE
- Gain Bandwidth (FT) is 150 to 450MHz
- Junction temperature is between –55 to 150℃
- Noise figure (NF) is 15dB
- Collector to emitter saturation voltage (VCE (SAT)) is3V
- AF amplifier device
- High voltage
- Low-speed switching
2SC945 transistor Pinout
| Pin Number | Pin Name | Description |
| 1 | Emitter | Current flows through the emitter terminal |
| 2 | Collector | Current flows through the collector |
| 3 | Base | The base is the trigger for the transistor |
2SC945 transistor package
The transistor package used at the 2SC945 device is the TO-92 package, it is a general-purpose transistor package mainly used at every common circuit, but the 2SC945 is not a common transistor.
The TO-92 is a package made with a combination of plastic and epoxy and also it’s a less compact package, so circuit design with this device will become less complex.
2SC945 transistor electrical specification description
The transistor 2SC945 is an AF amplifier high-frequency device, in this section we try to explain the electrical specs separately.
Voltage specs
The voltage specification of the 2SC945 transistor will be explained with terminal voltage specs, here we have collector to base voltage is 50V, collector to emitter voltage is 40V and emitter to base voltage is 5V, the voltage values state that 2SC945 transistor is a medium power device.
Current specs
The collector current value is 0.1A, the current value of the transistor shows the load capacity.
Dissipation specs
The power dissipation of this transistor will be 250Mw, it is the power capacity of the 2SC945 transistor, and we can also explain power dissipation as the heat capacity of the transistor.
Current gain specs
The current gain value is between 50 to 185hFE, it is an important value at amplifier and voltage regulation-related applications.
Transition frequency/ Bandwidth frequency specs
The transition frequency value is explained with gain-bandwidth which is between 150 to 450MHz, this is an important spec for amplifier and switching-based applications.
Junction temperature
The junction temperature of -55 to 150℃, this is the most common temperature value for a medium power transistor device.
Noise figure
The noise figure value for the 2SC945 transistor is 15dB, the noise figure value is moderate for an amplifier device.
2SC945 transistor DATASHEET
If you need the datasheet in pdf please click this link
2SC945 transistor equivalent
The transistors such as 2SC1815, 2SC2458, 2SC3198, 2SC3199, C945, and KSC3198 are the equivalent transistors for 2SC945.
Each of the transistors in this list had almost the same electrical specifications, we can easily replace 2SC945 with these transistors.
2SC945 vs 2SC1815 vs 2N3904
The table will explain the comparison between 2SC945 vs 2SC1815 vs 2N3904, electrical specs of each transistor will give us an idea about the transistor.
| Characteristics | 2SC945 | 2SC1815 | 2N3904 |
|---|---|---|---|
| Collector to base voltage (VCB) | 50V | 60V | 60V |
| Collector to emitter voltage (VCE) | 40V | 50V | 40V |
| Emitter to base voltage (VEB) | 5V | 5V | 6V |
| Collector current (IC) | 0.1A | 0.15A | 200mA |
| Power dissipation | 250mW | 0.4W | 625mW |
| Junction temperature (TJ) | 150°C | 150°C | 150°C |
| Transition frequency (FT) | 150MHZ | 80MHZ | 250MHZ |
| Noise (N) | 15dB | 1dB | 6dB |
| Gain (hFE) | 50 to 185hFE | 70 to 700hFE | 30 to 300hFE |
| Package | TO-92 | TO-92 | TO-92 |
The electrical specification table of three transistors states that each of the transistors had almost the same specifications.
The difference we can only see at transition frequency and DC current gain values, the transition frequency are higher at 2N3904 and 2SC1815 had higher DC gain value.
2SC945 transistor characteristics
The figure shows the graphical representation of collector current vs collector to emitter voltage, at each base current value, the collector current will rise at a level.
And the voltage becomes perpendicular with each range, the graph shows that at a certain level the collector current becomes constant.
The figure shows the characteristics curve of the 2SC945 transistor, the graph will be drawn between DC current gains vs collector current.
