How to Use MPX5500DP: Examples, Pinouts, and Specs

The MPX5500DP is a piezoresistive pressure sensor that provides a linear voltage output proportional to the applied pressure. It is designed for high accuracy and stability, making it suitable for a wide range of applications. This sensor is commonly used in automotive systems (e.g., engine control), industrial equipment (e.g., pneumatic systems), and medical devices (e.g., respiratory monitoring). Its dual-port design allows for differential pressure measurements, making it versatile for both gauge and differential pressure sensing.

The MPX5500DP is a high-performance pressure sensor with the following key specifications:

• Pressure Range: 0 to 500 kPa (0 to 72.5 psi)
• Output Voltage: 0.2 V to 4.7 V (proportional to pressure)
• Supply Voltage: 4.75 V to 5.25 V
• Accuracy: ±1.5% of full-scale span
• Operating Temperature: -40°C to +125°C
• Response Time: 1 ms
• Port Configuration: Dual port (differential pressure sensing)
• Package Type: Standard plastic package with barbed ports

The MPX5500DP has a 6-pin configuration. The table below describes each pin:

1. Power Supply: Connect the Vcc pin (Pin 3) to a regulated 5 V power supply and the GND pin (Pin 2) to the ground of the circuit.
2. Output Signal: The Vout pin (Pin 1) provides an analog voltage output proportional to the applied pressure. This output can be read using an analog-to-digital converter (ADC) on a microcontroller or data acquisition system.
3. Pressure Ports: The MPX5500DP has two ports:
   • Port P1: Positive pressure port (high-pressure side).
   • Port P2: Negative pressure port (low-pressure side). For gauge pressure measurements, leave P2 open to the atmosphere.

• Filtering: Add a decoupling capacitor (e.g., 0.1 µF) between Vcc and GND to reduce noise and improve stability.
• Pressure Range: Ensure the applied pressure does not exceed the sensor's maximum rating of 500 kPa to avoid damage.
• Mounting: Secure the sensor to prevent mechanical stress on the ports, which could affect accuracy.
• Temperature Compensation: The MPX5500DP includes internal temperature compensation, but ensure the operating environment stays within the specified temperature range for optimal performance.

The MPX5500DP can be easily interfaced with an Arduino UNO to measure pressure. Below is an example circuit and code:

• Connect Pin 1 (Vout) of the MPX5500DP to the Arduino's A0 pin.
• Connect Pin 2 (GND) to the Arduino's GND.
• Connect Pin 3 (Vcc) to the Arduino's 5V pin.

// MPX5500DP Pressure Sensor Example
// Reads the analog output from the sensor and calculates the pressure in kPa.

const int sensorPin = A0; // Analog pin connected to Vout of MPX5500DP
const float Vcc = 5.0;    // Arduino supply voltage (5V)
const float VoutMin = 0.2; // Minimum output voltage of MPX5500DP (0.2V)
const float VoutMax = 4.7; // Maximum output voltage of MPX5500DP (4.7V)
const float pressureMax = 500.0; // Maximum pressure in kPa

void setup() {
  Serial.begin(9600); // Initialize serial communication
}

void loop() {
  int sensorValue = analogRead(sensorPin); // Read analog value (0-1023)
  float voltage = (sensorValue / 1023.0) * Vcc; // Convert to voltage
  float pressure = ((voltage - VoutMin) / (VoutMax - VoutMin)) * pressureMax;

  // Print the pressure value to the Serial Monitor
  Serial.print("Pressure: ");
  Serial.print(pressure);
  Serial.println(" kPa");

  delay(1000); // Wait 1 second before the next reading
}

1. No Output Voltage:

   • Check the power supply connections (Vcc and GND).
   • Ensure the supply voltage is within the specified range (4.75 V to 5.25 V).

2. Inaccurate Pressure Readings:

   • Verify that the pressure ports are correctly connected (P1 for high pressure, P2 for low pressure).
   • Ensure there is no blockage or leakage in the pressure lines.
   • Check for electrical noise and add a decoupling capacitor if necessary.

3. Output Voltage Stuck at Maximum or Minimum:

   • Ensure the applied pressure is within the sensor's range (0 to 500 kPa).
   • Inspect the sensor for physical damage or contamination.

Q: Can the MPX5500DP measure vacuum pressure?
A: Yes, the MPX5500DP can measure vacuum pressure when P1 is exposed to a lower pressure than P2.

Q: Is the MPX5500DP waterproof?
A: No, the MPX5500DP is not waterproof. Avoid exposing the sensor to liquids or high humidity.

Q: Can I use the MPX5500DP with a 3.3 V microcontroller?
A: The MPX5500DP requires a 5 V supply for proper operation. Use a level shifter or voltage divider to interface its output with a 3.3 V microcontroller.