The TIP127 is a PNP Darlington transistor commonly used for high-power switching applications. Here is the complete datasheet for this transistor:
Electrical Characteristics:
- Collector-Emitter Voltage (VCEO): 100V
- Collector-Base Voltage (VCBO): 100V
- Emitter-Base Voltage (VEBO): 5V
- Collector Current (IC): 5A (continuous), 8A (peak)
- Base Current (IB): 50mA (continuous), 100mA (peak)
- Power Dissipation (PD): 2W
- Minimum hFE or DC Current gain: 1000
Thermal Characteristics:
- Junction Temperature (Tj): -65°C to 150°C
- Thermal Resistance - Junction to Case (RθJC): 3.125°C/W
- Thermal Resistance - Junction to Ambient (RθJA): 62.5°C/W
Pin Configuration:
As shown in the above figure, the TIP127 transistor has three pins: the collector (C), the base (B), and the emitter (E). The pinout configuration is as follows:
- Pin 1: Base (B)
- Pin 2: Collector (C)
- Pin 3: Emitter (E)
Internal Darlington Configuration
The TIP127 is a PNP Darlington transistor which has two PNP transistors configured with each other, as shown in the following diagram:
How to Switch ON TIP127 Transistor
Since the TIP127 is a PNP transistor, it can be switched ON by applying a negative potential to it base pin, as shown in the following circuit diagram:
Package Information:
The TIP127 transistor is available in the TO-220 package, which is a through-hole package with a single mounting hole. The package dimensions are as follows:
- TO-220 Package: 10.67mm x 15.87mm x 4.83mm
Typical Applications:
The TIP127 transistor is commonly used in high-power switching applications, such as:
- Power supplies
- Motor control
- Lamp dimming
- Solenoid control
- Audio amplifiers
- High-current drivers
Limitations:
- Maximum Collector Current: 5A (continuous)
- Maximum Power Dissipation: 2W
- Maximum Voltage: 100V
Other Features:
- Darlington Configuration
- High DC Current Gain (hFE)
- Low Saturation Voltage (VCEsat)
Note: This information is taken from the TIP127 datasheet published by ON Semiconductor. Actual values may vary based on specific manufacturer and production batch.
Questions & Answers
how do we make its output voltage adjustable. this topic is rarely discussed in electronics. Many concentration is on NPN TRANSISTORS
Do you mean with an emitter follower configuration? You just have to do the opposite of what you do in an NPN based emitter follower…
yes. ok I get it now. meaning the positive voltage has to enter through the emitter this time and then the output is through the collector as the pot is adjusted .
Yes, the load and the positive supply must be in series with the emitter, and the base should be connected to a potential divider which provides a variable voltage across the base/ground of the PNP transistor. The collector can be directly connected to the ground.