Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [2n2222]

9 questions
7
votes
5 answers

2N2222 burning out in the lab at 22 V

According to the datasheet, a 2N2222 can handle \$V_{CE(max)}\$ up to \$40\ V\$. However, in the lab, I've seen different 2N2222s fail (get turned on) and burn with the below circuit. I need to know why this happens. My transistor starts burning…
John Jin
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2
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2 answers

Creating a 3.3 V audio amplifier using an NPN 2N2222 transistor

It has been way too long since I did anything with transistor amplifiers. I am trying to find an example of a 3.3 V NPN transistor amplifier preferably based around a 2N2222 transistor. I have lost much knowledge about biasing and even schematic…
Collin
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1
vote
1 answer

Make a switchable steady 5 V output circuit

I am looking to make a very accurate steady 5V power supply that can be switched on and off using the digital IO pins on an Arduino. I planned to use a 9V power supply connected to a 2N2222 transistor switched on/off using the Arduino and the…
R Doyle
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1
vote
2 answers

How to calculate the resistor values for the zener diode and the BJT base?

I try to convert ~12V signal from a car button (the input voltage can be from 10V to 14V) to a logic level signal for MCU, but the signal should to be inverted (1 = 0, 0 = 1). Below is my schema, but I'm not sure how to calculate the resistor values…
Osoian Marcel
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0
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1 answer

Simulating BJT 2N2222 in LTspice. 5 mA collector current when B and E shorted

I am simulating NPN 2N2222 in LTspice. When I short base and emitter, the collector has peak up to 6 mA. Should not it be in terms of nA when there is 0 V between base and emitter? Can you please describe what is going on?
Walter Nürnberger
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2 answers

Homemade Doorbell - Issues with transistor and battery

I'm making a doorbell and i've tested it on my breadboard where it works perfectly fine. However, when I transfer it to a soldered circuit I have some issues. The switching of the transistor is ok, and works with my reciever/transmitter circuit. But…
Aleksander Lauridsen
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0
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2 answers

Driving a 12 V DC pump using Atmega16 Microcontroller and a 2N2222a transistor but it is not working?

I am implementing a system using an ATmega 16, a 12V/ 0.4mA/4.8W DC water pump, a 2N2222a transistor, a 1N4001 diode, a resistor and, a 12V Power Supply. However, whenever I test the circuit with the code I wrote, the pump does not turn on but when…
Saeed Bowman
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0
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1 answer

Control 12V 90mA alarm from 2N2222

I have an alarm rated for 12V 90mA. I want to turn the alarm on/off with a 2N2222. The base of the 2N2222 is connected to an ESP32. Circuit diagram is attached. Will it work?
ROBERT
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0
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2 answers

How do I saturate an NPN transistor for switching?

I want to use a 12F675 to turn on two LEDs. After a little research, I decided to use a 2N2222A NPN transistor and 2 LEDs in series (2V-drop 20mA consumption.) As I read in datasheet, microcontroller provides 20mA on the output pins. Can you please…
SkePsis
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