2EZ9.1D5/TR8 Datasheet/PDFA 2EZ9.1D5/TR8 is an electronic device that is used as a voltage regulator. It combines a Zener diode (stable voltage regulator) and an NPN bipolar transistor in a single package. The device is primarily employed for powering low-voltage, low-current loads such as logic and microcontrollers, blinking LEDs, and so on.The 2EZ9.1D5/TR8 offers reliable stability with a minimum supply voltage of 2.5V and a maximum voltage drop of 0.7V.
Application Fields
The 2EZ9.1D5/TR8 can find application in a variety of situations, particularly when a small, reliable power source is required. Its uses include:
- For protecting which can be installed for a checkup of equipment overvoltage
- For generating a voltage reference for logic circuits
- For controlling blinks of LED. In this case, the LED is connected to the transistor collector and the base is connected to a resistor and a timing capacitor.
Working Principle
The 2EZ9.1D5/TR8 consists of a Zener diode and an NPN bipolar transistor (see diagram). The integrated circuit is designed to regulate the output voltage at a set level, as determined by the Zener diode. The transistor works under a constant current, driving the transistor’s operating voltage to the “zero voltage” of the Zener diode—the point at which the voltage drop is zero.
The Zener diode\'s voltage determines the output voltage. It is connected in reverse-bias configuration to the transistor base. This creates a stable reference for the transistor, and the output voltage is regulated and remains constant as long as the input voltage stays within the specified limits.
The current flowing through the transistor is determined by the B-E junction of the transistor and the resistance of the base resistor. Since the current flow is constant, the voltage drop across the resistor is also constant, ensuring a constant output voltage.
Conclusion
The 2EZ9.1D5/TR8 is a versatile and reliable voltage regulator device. It is easy to use and is designed to produce a constant output voltage. Its use, as discussed above, is ideal in situations where a low-voltage, low-current load is required.