How to Use Stabil 7805 TO92: Examples, Pinouts, and Specs

The Stabil 7805 TO92, manufactured by ST, is a compact and reliable voltage regulator designed to provide a fixed output of 5V. It is part of the 78xx series of voltage regulators and is housed in a TO-92 package, making it ideal for low-power applications where space is a constraint. This component is widely used in electronic circuits to ensure a stable and regulated voltage supply, protecting sensitive components from voltage fluctuations and noise.

• Power supply regulation for microcontrollers, sensors, and other low-power devices.
• Voltage stabilization in battery-powered circuits.
• Protection of sensitive electronic components from overvoltage.
• Use in DIY electronics projects and prototyping.

The Stabil 7805 TO92 is designed to deliver consistent performance under a range of operating conditions. Below are its key technical specifications:

The Stabil 7805 TO92 has three pins, as detailed in the table below:

1. Connect the Input Voltage: Attach the unregulated DC voltage source (7V to 20V) to the Input pin (Pin 1).
2. Ground Connection: Connect the Ground pin (Pin 2) to the circuit's ground.
3. Output Voltage: The regulated 5V output will be available at the Output pin (Pin 3). Connect this pin to the load requiring a 5V supply.
4. Add Capacitors: For improved stability and noise filtering, connect a 0.33µF capacitor between the Input pin and ground, and a 0.1µF capacitor between the Output pin and ground.

• Ensure the input voltage is at least 2V higher than the desired output voltage (minimum 7V for a 5V output).
• Do not exceed the maximum output current of 100mA to avoid overheating or damage.
• Use proper heat dissipation techniques if the regulator operates near its maximum current limit.
• Place the capacitors as close as possible to the regulator pins to minimize noise and improve stability.

The Stabil 7805 TO92 can be used to power an Arduino UNO by providing a stable 5V supply. Below is an example circuit and code to demonstrate its usage:

1. Connect a 9V battery to the Input pin of the 7805.
2. Connect the Ground pin to the Arduino's GND pin.
3. Connect the Output pin to the Arduino's 5V pin.

// Example code to blink an LED using Arduino UNO powered by Stabil 7805 TO92
// Ensure the 7805 regulator is providing a stable 5V to the Arduino's 5V pin.

const int ledPin = 13; // Pin connected to the onboard LED

void setup() {
  pinMode(ledPin, OUTPUT); // Set the LED pin as an output
}

void loop() {
  digitalWrite(ledPin, HIGH); // Turn the LED on
  delay(1000);               // Wait for 1 second
  digitalWrite(ledPin, LOW);  // Turn the LED off
  delay(1000);               // Wait for 1 second
}

1. No Output Voltage:

   • Ensure the input voltage is within the specified range (7V to 20V).
   • Check for proper connections to the Input, Ground, and Output pins.
   • Verify that the capacitors are correctly placed and functional.

2. Overheating:

   • Ensure the output current does not exceed 100mA.
   • Use a heatsink or improve ventilation if the regulator operates near its maximum current.

3. Output Voltage Fluctuations:

   • Add or replace the input and output capacitors to improve stability.
   • Check for noise or interference in the input voltage source.

4. Component Damage:

   • Verify that the input voltage does not exceed 20V.
   • Avoid reverse polarity connections to prevent damage.

Q: Can the Stabil 7805 TO92 power high-current devices?
A: No, the maximum output current is 100mA. For higher current requirements, consider using a 7805 in a TO-220 package.

Q: Do I need to use capacitors with the Stabil 7805 TO92?
A: Yes, capacitors are recommended for stability and noise filtering. Use a 0.33µF capacitor on the input and a 0.1µF capacitor on the output.

Q: Can I use the Stabil 7805 TO92 with an input voltage below 7V?
A: No, the input voltage must be at least 7V to ensure proper regulation and a stable 5V output.

Q: Is the Stabil 7805 TO92 suitable for battery-powered circuits?
A: Yes, it is ideal for low-power battery-operated circuits, provided the input voltage is within the specified range.