The **154N-030G-R** is a high-performance, media-isolated, piezoresistive silicon pressure sensor produced by **TE Connectivity (Measurement Specialties)**. It is specifically designed for applications where the sensor must interface with corrosive or harsh liquids and gases. --- ### ## 1. Key Specifications | Feature | Specification | | :--- | :--- | | **Pressure Range** | 0 to 30 psi (Pounds per Square Inch) | | **Pressure Type** | Gage (Measured relative to atmospheric pressure) | | **Sensor Type** | Piezoresistive Silicon | | **Output Type** | Voltage (Millivolt Bridge) | | **Operating Temp** | -40°C to +125°C | | **Material** | 316L Stainless Steel | | **Accuracy** | ±0.1% Span (linearity) | --- ### ## 2. Core Components and Design The 154N series utilizes a sophisticated mechanical design to protect the sensitive electronics from the environment: 1. **316L Stainless Steel Housing:** The outer casing and diaphragm are made of surgical-grade stainless steel, ensuring resistance to corrosion. 2. **Silicone Oil Fill:** The internal cavity between the stainless steel diaphragm and the silicon sensing chip is filled with silicone oil. This oil transfers the external pressure to the chip without exposing the chip to the media. 3. **Piezoresistive Die:** The heart of the sensor is a micro-machined silicon die that changes its electrical resistance when mechanical stress (pressure) is applied. 4. **Ceramic Compensation Board:** The "-R" suffix indicates the inclusion of a ceramic substrate with thick-film resistors. These are used for laser-trimmed temperature compensation and offset calibration. --- ### ## 3. Electrical Connection & Pinout The device typically features a ribbon cable or flexible leads. The electrical circuit is a standard **Wheatstone Bridge**. | Pin Number | Function | Description | | :--- | :--- | :--- | | 1 | -Output | Negative Differential Output | | 2 | -Excitation | Negative Supply Voltage | | 3 | +Output | Positive Differential Output | | 4 | +Excitation | Positive Supply Voltage | --- ### ## 4. Applications Due to its robust 316L construction, the 154N-030G-R is commonly found in: * **Medical Instruments:** Dialysis machines and infusion pumps. * **Process Control:** Monitoring fluids in industrial pipelines. * **Freshwater/Wastewater:** Level and pressure monitoring. * **HVAC Systems:** Refrigerant and hydraulic pressure measurement. --- ### ## 5. Implementation Note Because this is an unamplified millivolt output sensor, you will typically need an **Instrumentation Amplifier** (like the AD623 or INA126) and a regulated DC power supply to interface it with a microcontroller (like an Arduino or ESP32).