How to Use LM4128-2.5VREF: Examples, Pinouts, and Specs

The LM4128-2.5VREF is a precision, low-dropout voltage reference that provides a fixed 2.5V output with high stability and low temperature coefficient. This component is ideal for providing a stable reference voltage in a variety of applications, including analog-to-digital converters (ADCs), digital-to-analog converters (DACs), power supplies, and battery-operated devices.

• Precision voltage reference for ADCs and DACs
• Portable instrumentation
• Power supply monitoring
• Battery-powered devices

The LM4128-2.5VREF offers excellent performance characteristics suitable for critical applications. Below are the key technical specifications:

To use the LM4128-2.5VREF in a circuit, connect the VIN pin to a supply voltage that is at least 1V higher than the desired output voltage to ensure proper operation. The VOUT pin should be connected to the point in the circuit where a stable reference voltage is needed. The GND pin must be connected to the system ground.

• Bypass the VIN pin with a 1µF ceramic capacitor placed as close as possible to the device pins to minimize noise.
• Avoid running high-current traces or noisy signal lines near the device to prevent interference.
• Ensure that the input voltage does not exceed the maximum specified limit to prevent damage to the device.
• Use proper ESD precautions when handling the device to avoid electrostatic damage.

• Output Voltage Fluctuation: Ensure that the input voltage is stable and that there is adequate bypass capacitance at the VIN pin.
• Device Heating: Check that the output current does not exceed the maximum rating of the device.

Q: Can the LM4128-2.5VREF be used with an Arduino UNO? A: Yes, it can be used to provide a stable reference voltage for analog readings with an Arduino UNO.

Q: What is the maximum input voltage for the LM4128-2.5VREF? A: The maximum input voltage is typically 12V, but always refer to the latest datasheet for the specific device limits.

Q: How can I improve the accuracy of my voltage reference in a high-temperature environment? A: Use a voltage reference with a low temperature coefficient and place it in a location with minimal temperature variation.

Below is an example of how to use the LM4128-2.5VREF with an Arduino UNO to take precise analog readings.

// Define the analog pin connected to the voltage reference
const int analogPin = A0;

void setup() {
  // Start the serial communication
  Serial.begin(9600);
  
  // Configure the analog reference to EXTERNAL
  analogReference(EXTERNAL);
}

void loop() {
  // Read the voltage on the analog pin
  int sensorValue = analogRead(analogPin);
  
  // Convert the reading to voltage
  float voltage = sensorValue * (2.5 / 1023.0);
  
  // Print the voltage to the Serial Monitor
  Serial.println(voltage);
  
  // Wait for a bit before reading again
  delay(1000);
}

Note: Before uploading the code, connect the VOUT pin of the LM4128-2.5VREF to the AREF pin on the Arduino UNO and ensure that the GND pin is connected to the Arduino's ground.

This documentation provides a comprehensive overview of the LM4128-2.5VREF voltage reference. For more detailed information, always refer to the manufacturer's datasheet.