Questions tagged [2n2222]
The 2n2222 tag has no usage guidance.
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Transistor latch
I've tried making multiple transistor latches and I'm able to get them working on the breadboard but everytime I try putting it on a prototype board the resistors changed their value. The one that ...
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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 ...
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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, ...
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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 ...
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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?
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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