TIP122 transistor
TIP122 transistor specification
- TIP122 is an NPN Darlington pair transistor device
- Collector to emitter voltage is 100V
- Collector to base voltage is 100V
- Emitter to base voltage is 5V
- Collector current is 5A
- Base current is 120mA
- Power dissipation is 65W
- DC current gain is 1000hFE
- Small signal DC current gain is 4hFE
- Junction temperature is between -65 to +150℃
- Collector to emitter saturation voltage (VCE (SAT)) is 2V
- Thermal resistance is 5℃/W
- Output capacitance is 200pF
- Medium power transistor device
- Low saturation voltage
- Low voltage complementary
- High gain
TIP122 transistor Pinout
| Pin Number | Pin Name | Description |
| 1 | Base | The base is the trigger for the transistor |
| 2 | Collector | Current flows through the collector |
| 3 | Emitter | Current flows through the emitter |
| 4 | Collector | The heat sink also acts as the collector terminal |
Darlington transistor
The figure shows the internetwork of Darlington transistors, they are also having NPN and PNP versions transistors.
As in the circuit, two transistors are been connected back to back to make a Darlington transistor network.
These types of transistors have high gain and higher amplification factor, this is possible due to the usage of two transistors.
TIP122 transistor package
TIP122 Darlington transistor had the device package of TO-220AB, it is a medium power transistor device.
TO-220AB package has two portions, the front portion is made with epoxy/ plastic material and the back portion is made to attach to the heat sink.
Marking the case
The marking of this transistor is TIP122 at the case
TIP122 transistor electrical specification description
In this section, we try to explain the electrical specification of the TIP122 transistor device.
Voltage specs
The terminal voltage specs of the TIP122 transistor are collector to emitter voltage and collector to base voltage is 100V and emitter to base voltage is 5V, the voltage specs show that TIP122 is a power supply application component.
The collector to emitter saturation voltage is 2V, it is the voltage value lesser than the base voltage.
Current specs
The collector current value of the TIP122 transistor is 5A, it is the current load capacity of the transistor device.
Dissipation specs
The power dissipation at the TIP122 transistor is 65W, the device dissipation mainly depends on the transistor package and overall capacity.
Current gain specs
The current gain value of TIP122 is 1000hFE, the DC current value shows that it is capable of amplifier and driver applications.
The small-signal current gain value of the TIP122 transistor is 4hFE, so in small-signal applications.
Junction temperature
The junction temperature of -65 to 150℃, and the TIP122 is a power transistor.
Thermal resistance
The thermal resistance of the TIP122 transistor case is 62.5℃/W
TIP122 Darlington transistor DATASHEET
If you need the datasheet in pdf please click this link
TIP122 transistor equivalent
The TIP122 transistor had equivalents such as TIP132, TIP102, BDT65B, 2N6045, 2SD2495, MJF122G and KSB601.
The electrical specifications of these transistors are the same, we can easily replace TIP122 transistors with these transistor devices.
TIP122 transistor complementary
TIP122 Darlington NPN transistors have complementary device TIP127 PNP Darlington transistor.
TIP122 vs TIP41C vs 2SD633
In the table below, we try to compare TIP122, TIP41C, and 2CD633 transistors, the electrical specification comparison is really helpful for circuit making.
| Characteristics | TIP122 | TIP41C | 2SD633 |
|---|---|---|---|
| Collector to base voltage (VCB) | 100V | 100V | 100V |
| Collector to emitter voltage (VCE) | 100V | 100V | 100V |
| Emitter to base voltage (VEB) | 5V | 5V | 5V |
| Collector to emitter saturation voltage (VCE (SAT)) | 2V | 1.5V | 0.9 to 2V |
| Collector current (IC) | 5A | 6A | 7A |
| Power dissipation | 65W | 65W | 40W |
| Junction temperature (TJ) | -65 to +150°C | -65 to +150°C | -55 to +150°C |
| Transition frequency (FT) | - | 3MHZ | - |
| Gain (hFE) | 1000hFE | 15 to 75hFE | 1000 to 150000hFE |
| Package | TO-220AB | TO-220 | TO-220AB |
TIP122 Darlington transistor applications
- General-purpose linear and switching applications
- General-purpose amplifier circuits
- Medium power linear switching
- Low-speed switching applications
- Speed controlling of motor
- Inverter circuits
- Rectifier circuits
- Audio system applications
- Power switching applications
- Preamp circuits
TIP122 transistor characteristics curves
The figure shows the DC current gain characteristics of the TIP122 transistor, the graph is plotted with dc current gain vs collector current.
At a fixed collector to emitter voltage, the DC gain value will increases from a lower value to a higher one and decrease at the end.
The figure shows the safe operating area of the TIP122 transistor, the graph is plotted with collector current vs collector to emitter voltage.
Main the switching speed of the TIP122 transistor are been given at the characteristic curve.
