2SA1943 transistor

2SA1943 specification
- 2SA1943 is a PNP epitaxial bipolar junction silicon power transistor device
- Collector to emitter voltage (VCE) is -250V
- Collector to base voltage (VCB) is -250V
- Emitter to base voltage (VEB) is -5V
- Collector current is –17A
- Base current is -1.5A
- Power dissipation is 40W
- DC current gain is 55 to 160hFE
- Transition frequency (FT) is 30MHz
- Junction temperature is between -50 to 150℃
- Collector to emitter saturation voltage (VCE (SAT)) is -0.4 to -3.0V
- Output capacitance (Co) is 360pF
- Thermal resistance, junction to the case is 83℃/W
- Power amplifier device
- High current capability
- High power dissipation
- High frequency
- High voltage
- Wide range of S.O.A for reliable operation
- Excellent gain
- LOW THD
2SA1943 Pinout

Pin Number | Pin Name | Description |
1 | Base | The base terminal is the trigger for the transistor |
2 | Collector | Current flow through the collector |
3 | Emitter | Current flows through the emitter |
2SA1943 transistor package
The 2SA1943 PNP transistor has a TO-264 transistor package, it is a high-power transistor package.
The main outer covering of the 2SA1943 PNP transistor package is made with epoxy/plastic material to withstand high-value temperatures and it makes the device less weight.
TO-264 is a through-hole package, so it had a hole at the center for attaching a heat sink with it. These device packages are been used in thyristors, MOSFET, integrated circuits, etc….
2SA1943 PNP transistor electrical specification description/ application
In this section, we try to explain the electrical specifications of the 2SA1943 PNP transistor, the detailed specs explanation will help us to understand more about this device.
Voltage specs
The voltage specifications of the 2SA1943 PNP transistor are collector to base voltage is -250V, collector to emitter voltage is -250V, and emitter to base voltage is -5V.
The collector to emitter saturation voltage is -0.4 to -3.0V, it is the switching voltage of the transistor.
Overall voltage specifications of the 2SA1943 transistor show that it is a high voltage transistor device that has a power supply and amplifier-based applications.
Current specs
The collector current value of the 2SA1943 transistor is -17A, which is the maximum load capacity of the device.
The base current value of the 2SA1943 transistor is -1.5A, and the base voltage is the switching current required for the transistor.
Overall current values of the 2SA1943 PNP transistor show that it is a high current device that is used for switching and power switching applications.
Dissipation specs
The power dissipation of the 2SA1943 PNP transistor is 150W, the device package made it a high dissipation transistor.
Current gain specs
The DC current gain of the 2SA1943 PNP transistor is 55 to 160hFE, the gain capacity of this device is low, and this is why this transistor has low amplification applications.
Transition frequency
The transition frequency value of the 2SA1943 transistor is 30MHz, these transistor devices had a moderate frequency range.
Junction temperature/ storage temperature
The junction temperature/ storage temperature of -50 to 150℃.
Thermal resistance
The thermal resistance of the 2SA1943 PNP transistor case is 0.83℃/W
Output capacitance
The output capacitance of the 2SA1943 transistor is 360pF
2SA1943 DATASHEET
If you need the datasheet in pdf please click this link
2SA1943 equivalent
The transistors 2SA1962, FJZ4215, 2STA2121, 2SA1986, KTA1962, MJW1302A, FJA4213, and 2SA2151A-Y are the equivalent devices of the 2SA1943 transistor. Each of the transistors had a similar set of electrical specifications, so we can easily replace the place of the 2SA1943 PNP transistor.
But we need to check and verify the voltage specs and PINOUT details of all equivalent devices before the replacement process because these specs are been very dangerous at the circuit level.
2SA1943 PNP complementary pair
The 2SC5200 NPN is the complementary pair of the 2SA1943 PNP transistor, combinations of these two transistors are been used in push-pull circuits and stereo amplifier circuits.
2SA1943 vs 2SA1986 vs 2SA1962
In this table, we list and compare the electrical specifications of 2SA1943, 2SA1986, and 2SA1962, this comparison will help us to know about these devices and support us in the replacement process.
Characteristics | 2SA1943 | 2SA1986 | 2SA1962 |
---|---|---|---|
Collector to emitter voltage (VCE) | -250V | -230V | -230V |
Collector to base voltage (VCB) | -250V | -230V | -230V |
Emitter to base voltage (VEB) | -5V | -5V | -5V |
Collector to emitter saturation voltage (VCE (SAT)) | -0.4 to -3.0V | -1.5 to -3.0V | -1.5 to 3.0V |
Collector current (IC) | -17A | -15A | -15A |
Base current | -1.5A | -1.5A | -1.5A |
Power dissipation | 150W | 150W | 130W |
Junction temperature (TJ) | -50 to +150°C | -55 to +150°C | -55 to +150°C |
Thermal resistance | 0.83℃/W | - | - |
Transition frequency (FT) | 30MHZ | 30MHZ | 30MHz |
Gain (hFE) | 55 to 160hFE | 55 to 160hFE | 55 to 160hFE |
Output capacitance | 360pF | 360pF | 360pF |
Package | TO-264 | TO-264 | TO-220 |
Each of these three transistors has a similar set of electrical specifications, the old version of the 2SA1943 transistor have -230V, so this shows that all these transistors have the same voltage values.
Only the collector current value of the 2SA1943 transistor is slightly higher than the other two transistor devices.
2SA1943 transistor applications
- High fidelity audio output amplifier circuit
- General purpose amplifier
- AF/RF circuit
- High current switching applications
- Push-pull circuit
- Stereo system
- Less slew rate device
- Medium power switching
- SMPS
- Relay driver
- Power supply circuit
- Inverter circuit
- Converter circuit
- Power control circuit
Characteristics curves of 2SA1943 PNP transistor

The figure shows static characteristics of the 2SA1943 PNP transistor, the graph plots with collector current vs collector to emitter voltage.
At different base current values, the 2SA1943 transistor produces a curved graph with collector current and collector-to-emitter voltage.

The figure shows the current gain characteristics of the 2SA1943 transistor, the graph plots with DC current gain vs collector current.
At different temperature values, the DC current gain increases from the highest point and becomes constant, and starts decreasing at the end.