#npn transistor

[futurebird]

my students and I made and gates out of NPN transistors today. I read someone made a whole computer from components like this (not logic ICs) MADNESS

[errl2nson]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--mosfets/dmg1026uv-7-diodes-incorporated-2129543

Transistor circuits, npn transistor, transistor switch, bjt transistor

Dual N-Channel 60 V 2.1 Ohm 0.45 pC 0.65 W Silicon SMT Mosfet - SOT-563

[rumd2rtzz]

What is a bipolar transistor, transistor manufacturers, high voltage transistor

PMBTA45 Series 500 V 0.15 A 300 mW NPN SMT Small Signal Transistor - SOT-23

[jmsh2ptt]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--bipolar-transistors/pmbta45-215-nexperia-9009695

What is a bipolar transistor, High voltage transistor, transistor manufacturers

PMBTA45 Series 500 V 0.15 A 300 mW NPN SMT Small Signal Transistor - SOT-23

[wlly2rley]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--bipolar-transistors/mmbta06lt1g-onsemi-9159854

Surface Mount NPN Silicon Transistor, Driver Transistor, what is transistor

MMBTA06L Series NPN 80 V 500 mA SMT Driver Transistor - SOT-23

[jhn22ddrr]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--bipolar-transistors/mmbta06lt1g-onsemi-7421506

Onsemi, MMBTA06LT1G, Transistors, Bipolar (BJT) Transistors

MMBTA06L Series NPN 80 V 500 mA SMT Driver Transistor - SOT-23

[jsmsh2rmn]

NPN/PNP Digital Transistor, transistor switch, Bipolar junction transistor

PUMH9 Series 50 V 100 mA Surface Mount NPN Small Signal Transistor - SOT-363

[jsut2rett]

What is bipolar transistor, bipolar junction transistor, high voltage transistor

PUMH9 Series 50 V 100 mA Surface Mount NPN Small Signal Transistor - SOT-363

[deliandiver]

DUT: Serge Gain Cell

[xeyers]

I had to discuss BJT-NPN transistors in school today for longer that I would like to and junction sounds like a very crunchy word to me so I drew a very crunchy kisser real quick

[vulpes-aestatis]

Trick or Treat!!

You get: sixteen (16) NPN transistors

[dyethin14]

Understanding Circuit Board Electronic Components: A Comprehensive Guide

In today's digital world, electronic devices have become an essential part of our daily lives. But what makes these devices tick? At the heart of every electronic device lies a circuit board—a masterpiece of tiny electronic components working together to perform complex tasks. In this article, we’ll dive deep into the fascinating world of circuit board electronic components, exploring each element’s role and how they contribute to the overall functionality of the device.

What is a Circuit Board?

A circuit board, often referred to as a PCB (Printed Circuit Board), is a flat board used to mechanically support and electrically connect various electronic components. These components work in unison to perform a specific task. Think of the circuit board as the skeleton and nervous system of an electronic device—it holds everything together and allows communication between parts.

Types of Circuit Boards

Single-sided PCB: Has one layer of conducting material.

Double-sided PCB: Contains two layers for components and connections.

Multi-layer PCB: Complex boards with multiple layers for advanced applications.

The Role of Electronic Components on a Circuit Board

Every electronic device you interact with is powered by a carefully designed circuit board filled with various components. These components might be tiny, but each one has a critical role in the operation of the device. Here's a breakdown of the most important electronic components you’ll find on a typical circuit board.

1. Resistors

Resistors are fundamental components that control the flow of electrical current. They resist the flow of electrons, hence the name "resistor." Their primary function is to reduce current flow, adjust signal levels, and divide voltages in a circuit. Without resistors, circuits would allow too much current to flow, potentially damaging other components.

Types of Resistors

Fixed resistors: Have a set resistance value.

Variable resistors: Allow adjustment of the resistance.

2. Capacitors

Capacitors store and release electrical energy in a circuit. They are often compared to small rechargeable batteries that quickly charge and discharge. Capacitors help smooth out fluctuations in voltage, filter noise, and store energy for future use.

Common Uses of Capacitors

Energy storage

Signal filtering

Voltage stabilization

3. Inductors

Inductors are components that store energy in a magnetic field when electrical current flows through them. They resist changes in current and are typically used in circuits to filter signals, manage power, and store energy.

Applications of Inductors

Power supplies

Radio frequency circuits

Noise suppression in circuits

4. Diodes

A diode is like a one-way valve for electricity, allowing current to flow in only one direction. They are vital in circuits to prevent reverse currents, which can damage components.

Types of Diodes

Light-emitting diodes (LEDs): Produce light when current flows through.

Zener diodes: Regulate voltage within a circuit.

5. Transistors

The transistor is a versatile component used to amplify or switch electronic signals. In essence, transistors are like tiny switches that turn signals on and off rapidly, making them essential in modern electronics.

Types of Transistors

NPN transistors: Allow current flow when a small voltage is applied to the base.

PNP transistors: Conduct when the base is negatively charged.

How Circuit Board Components Work Together

In a circuit, each component has a specific role, and together they form a cohesive system. For example:

Capacitors and resistors may work together to filter signals or smooth out voltage fluctuations.

Transistors and diodes ensure that signals are amplified or directed properly.

Integrated circuits handle the complex tasks, processing data, and controlling the overall system.

Choosing the Right Components for Your Circuit Board

When designing or repairing a circuit board, choosing the correct components is crucial. Some factors to consider include:

Voltage requirements

Power consumption

Signal type and frequency

Physical size and compatibility

Conclusion

Circuit boards are an integral part of any electronic device. The various components on the board each play a specific role in ensuring the device functions as intended. Understanding these components, from resistors to integrated circuits, is essential for anyone working with electronics, whether you're designing a new system or troubleshooting an existing one.

[nhaneh]

figures all my regular BJT transistors are the wrong type

loads of NPNs but not a single PNP in sight welp

[fuzzkaizer]

DIY - transistors

- Transistor Fabrication: So Simple A Child Can Do It - by  Mike Szczys

- how to make npn & pnp transistor at home

- Homemade Field Effect Transistor (FET)

-  FET Transistor Homemade From Cadmium Sulfide Photocell.

- Amateur Scientist - DIY FET/home-made transistor Scientific American June 1970: (2008.04.15:3 materials#1 research#140)

... not that easy, after all!

[quartz-components]

2SC5200 Transistor is an NPN Power Transistor manufactured by Toshiba. It has collector continuous current of 15A and a Collector-Emitter voltage of 230V. The base current of this transistor is about 1.5A and the Emitter base voltage is 5V.

[darkbutterflyrc]

Morseduino keyboard based CW keyer

Based on an Arduino nano and CardKB mini keyboard. The parts you need to build it are

Arduino nano

CardKB mini keyboard

BC547 NPN transistor

1K resistor

5v reed relay

Socket for the reed relay

Stereo jack for the output

Two on-off-on switches, for speed and power

3D printer to make the enclosure

link to enclosure below

Wire up the speed switch with the centre pin to D13 of the Arduino, this is the reference pin. Connect the either side of the speed switch to D2 and D3 respectively

Wiring up the relay

The diode is not needed with a reed relay IC

The Arduino code

You will need this for the hardware to work, copy and paste it into Arduino IDE. Please respect my work and leave the top comment in.

/*

(c) 12/10/2024 Morseduino by Robert Rayner, M0YNW

This software has no warranty and you use it at your own risk.

*/

#include <Wire.h>

// Define pins for relay and LED

const int relayPin = 7; // relay output

const int ledPin = LED_BUILTIN; // built in LED (specify pin number if using an external LED)

const int speedSwitchA = 2;  // Pin connected to one side of the switch

const int speedSwitchB = 3;  // Pin connected to the other side of the switch

const int fastWPM = 20; // Fast speed (20 WPM)

const int slowWPM = 12; // Slow speed (12 WPM)

int wpm = fastWPM;  // Default WPM is set to fast

// Morse code timing variables

int dotDuration, dashDuration, elementSpace, letterSpace, wordSpace;

// Morse code representation for characters (A-Z, 0-9, /, =, . ?)

const char* morseCodeMap[43] = {

    ".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", ".---",  // A-J

    "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.", "...", "-",   // K-T

    "..-", "...-", ".--", "-..-", "-.--", "--..",                           // U-Z

    "-----", ".----", "..---", "...--", "....-", ".....", "-....",          // 0-5

    "--...", "---..", "----.",                                              // 6-9

    "-..-.", "..--..", "-...-", ".-.-.-"                                     //Special characters: / . ? =

};

// CardKB I2C address

#define CARDKB_ADDR 0x5F

// Function to map character to Morse code

const char* getMorseCode(char c) {

    if (c >= 'A' && c <= 'Z') {

        return morseCodeMap[c - 'A'];

    } else if (c >= '0' && c <= '9') {

        return morseCodeMap[26 + (c - '0')];

    } else if (c == '/') {

        return morseCodeMap[36]; // Morse for /

    } else if (c == '?') {

        return morseCodeMap[37]; // Morse for ,

    } else if (c == '=') {

        return morseCodeMap[38]; // Morse for =

    } else if (c == '.') {

        return morseCodeMap[39]; // Morse for .

    } else {

        return ""; // Return empty for unsupported characters

    }

}

// Function to read the slide switch and set WPM

void readSpeedSwitch() {

    // Read both switch states with internal pull-up resistors enabled

    int switchAState = digitalRead(speedSwitchA);

    int switchBState = digitalRead(speedSwitchB);

    // Update WPM if one switch is high and the other is low

    if (switchAState == LOW && switchBState == HIGH) {

        wpm = fastWPM;  // Set WPM to fast speed (20 WPM)

    } else if (switchAState == HIGH && switchBState == LOW) {

        wpm = slowWPM;  // Set WPM to slow speed (12 WPM)

    }

    // Update timing variables based on the current WPM

    updateWpmTiming();

}

// Function to transmit Morse code

void transmitMorse(const char* morse) {

    while (*morse) {

        if (*morse == '.') {

            digitalWrite(relayPin, HIGH);

            digitalWrite(ledPin, HIGH); // Turn on LED

            delay(dotDuration);

            digitalWrite(relayPin, LOW);

            digitalWrite(ledPin, LOW); // Turn off LED

            delay(elementSpace);

        } else if (*morse == '-') {

            digitalWrite(relayPin, HIGH);

            digitalWrite(ledPin, HIGH); // Turn on LED

            delay(dashDuration);

            digitalWrite(relayPin, LOW);

            digitalWrite(ledPin, LOW); // Turn off LED

            delay(elementSpace);

        }

        morse++;

    }

    delay(letterSpace); // Space between letters

}

// Function to read a key from CardKB

char readCardKB() {

    char key = '\0';  // Initialize with null character

    Wire.requestFrom(CARDKB_ADDR, 1);  // Request one byte from the CardKB

    if (Wire.available()) {

        key = Wire.read();  // Read the byte from the CardKB

    }

    return key;  // Return the key (or null if nothing was read)

}

// Update WPM and timing variables based on new WPM

void updateWpmTiming() {

    dotDuration = 1200 / wpm;

    dashDuration = dotDuration * 3;

    elementSpace = dotDuration;

    letterSpace = dotDuration * 3;

    wordSpace = dotDuration * 7;

}

void setup() {

    Serial.begin(9600);

    pinMode(relayPin, OUTPUT);

    pinMode(ledPin, OUTPUT); // Set the LED pin as OUTPUT

    Wire.begin();  // Initialize I2C communication with the CardKB

    // Enable internal pull-up resistors for the switch pins

    pinMode(speedSwitchA, INPUT_PULLUP);

    pinMode(speedSwitchB, INPUT_PULLUP);

    digitalWrite(13, HIGH); //connect this to the centre pin of the speed switch

    updateWpmTiming();  // Set initial WPM and timing values

}

void loop() {

    // Read the current position of the slide switch

    readSpeedSwitch();

    // Read key from CardKB

    char c = readCardKB();

    if (c != '\0') {  // If a key was pressed

        Serial.print("Key pressed: ");

        Serial.println(c);

        const char* morse = getMorseCode(toupper(c)); // Convert to uppercase and get Morse code

        if (morse[0] != '\0') { // If valid Morse code

            transmitMorse(morse);

        } else if (c == ' ') { // Handle space between words

            delay(wordSpace);

        }

    }

}