The Superior Architecture for Sensing Pressure

Superior Sensor Technology has developed the innovative NimbleSenseTM architecture which allows for the creation of highly advanced pressure sensing systems using a versatile design toolbox of technology building blocks. By enhancing system performance and providing cost-effective manufacturing solutions, this fully integrated platform is considered the industry’s first System-in-a-Sensor.

Through the incorporation of processing intelligence, signal path integration, and proprietary algorithms, the NimbleSense architecture facilitates sensor integration, enabling maximum performance. With the option to choose from a range of tested and proven building blocks, Superior Sensor Technology’s design experts can expertly integrate the most suitable blocks into a pressure sensor sub-system that optimizes performance for the specific application requirements of each customer.

This approach offers a considerable degree of design flexibility, allowing users to rapidly develop the pressure sensing solution necessary for their end product. With the NimbleSense architecture’s technology building blocks, users can expect up to 10x better performance and an array of application-specific features.

At the heart of the NimbleSense architecture and System-in-a-Sensor method lies a key component: flexibility. This innovative technology empowers you to swiftly design the sensor into your product, streamline multiple product lines using a single sensor, integrate new application-specific features and functions, and lower system costs through fewer components and enhanced product reliability. With customer input driving constant innovation, the Superior Sensor Technology engineering team regularly introduces new building blocks into the NimbleSense architecture.

Multi-Range Explainer Video

Pressure Switch Explainer Video

Z-Track Explainer Video

A single device can accommodate up to eight different pressure ranges, with each range being factory-calibrated and optimized to maintain consistent total error band, accuracy, and stability. This alleviates the complexity and complications associated with working with multiple sensors. Utilizing a Multi-Range part streamlines both the design and manufacturing process, eliminating the need for researching, purchasing, and integrating numerous parts.

Implementing the same component in all designs enhances efficiency and ease, and pressure adjustments are conveniently controlled through a single software command. Moreover, Multi-Range provides the added benefit of a singular inventory item, adding value and convenience to manufacturing operations. In summary, the value of Multi-Range is apparent to both design and manufacturing teams alike.

Multi-Range Comparison

Benefits of Multi-Range Technology include:

  1. Design flexibility with the ability to adjust pressure range throughout the development cycle
  2. Simplified product design with one sensor replacing up to 8 different sensors
  3. Ability to quickly develop product variants at different pressure ranges without changing hardware design
  4. Greater economies of scale by purchasing larger quantities of the same product
  5. Reduced manufacturing complexity and costs due to simplified calibration of sensors
  6. Up to 8x reduction in sensor inventory costs and product obsolescence
  7. Allows manufacturers to build fewer product variants, significantly lowering working capital requirements and inventory

To ensure precise and reliable medical readings, the company has developed its proprietary Z-Track technology that eliminates zero drift, which is crucial for accurate readings in medical devices like Spirometers. Z-Track enhances the accuracy of spirometers, resulting in more effective diagnoses and better treatment plans.

This technology maintains minimal zero-point deviation irrespective of the elapsed time, and combined with the Superior’s position insensitivity capability, the company’s pressure sensors offer the most accurate readings for all types of spirometry equipment. Users can rely on Z-Track technology for virtually error-free readings, regardless of the spirometer’s positioning or use. By employing Z-Track, we not only eradicate zero errors, but also guarantee that all readings are precise, reliable, and valuable for informed medical decisions.

Z-Track Graph

Benefits of Z-Track Technology include:

  1. Eliminate zero errors to ensure the most accurate spirometer readings in the industry
  2. Consistent performance regardless of elapsed time
  3. Extremely fast data transfer rate
  4. More effective medical diagnoses and treatment plans

By directly controlling motors, valves, and actuators, closed-loop control enhances the ability to establish and sustain flow rates through pressure management. Superior provides the option to integrate this capability into the sensor, allowing for more efficient control of flow rates and maintenance of flow rate targets.

Basic Control Loop System

Superior’s integrated closed-loop control design considerably reduces loop delays in electronic circuits by up to 100 times. This solution also removes the requirement to develop a complex, external control loop system, leading to more efficient, reliable, and cost-effective products. The benefits of an integrated closed-loop control cannot be overstated, especially in medical respiratory devices such as CPAP, HVAC systems, UAVs, and in products for measuring air quality.

Displayed in the diagram below is a block layout depicting the implementation of a superior closed-loop control system for an air quality application. For accurate measurement of air quality, it is essential to uphold a steady and predetermined airflow through the viewing window. The differential pressure measured across the venturi serves as a direct indication of the flow entering the viewing window. By setting a target pressure level across the venturi, the differential pressure sensor automatically adjusts the pump drive, up or down, to maintain the aimed differential pressure and sustain an even airflow into the viewing window. The utilization of the NimbleSense closed loop circuit, in combination with the company’s exclusive noise filtering technology, successfully reduced loop delay by more than 100 times.

CLC flow

Benefits of the integrated closed-loop control include:

  1. Greatly reduce loop delays to improve the accuracy and responsiveness of your product
  2. Improve the reliability of your product by eliminating discrete parts
  3. Reduce your overall system costs
  4. Minimize system power and heat
  5. Simplify your product design
  6. Speed your time to market

Superior’s cutting-edge digital filter is a multi-order filter that leverages advanced filtering capabilities at the front end of the sub-system to eradicate critical noise caused by fans, blowers, or other dry air/gas sources before they reach the pressure-sensing sub-system. This is accomplished using the NimbleSense advanced filtering capability, which eliminates sensor-induced mechanical noise before it becomes an error signal that can negatively impact overall system performance. By replacing a competing component in customer deployments, our sensor has produced a more than 10-fold reduction in sensor-induced noise, significantly enhancing the SNR of the sensor output. This improvement is even more substantial in very low-pressure systems.

By incorporating both standard and optional digital filters, this feature offers considerably better noise reduction and eliminates the need to design an external filtering system, leading to more efficient, reliable, and cost-effective products. Our advanced digital filtering is fine-tuned for each application to ensure that mixed sampling noise is well below the noise floor. By eradicating mechanical noise, we maximize the overall performance of the system.

Below is an example of a 4th-order FIR filter that has been specifically designed to eliminate pump noise above 50 Hz, which has an equal magnitude of noise as the signal being monitored. The graphs illustrate the outcome of Superior’s advanced digital filter.

Updated ADF transfer

Benefits of the advanced digital filtering technology include:

  1. Greatly reduced system noise levels by 10x or more, especially important in very low pressure applications. For noise prone systems, an improvement of 100x to 1000x is not unreasonable.
  2. Eliminate noise sources such as fans and blowers before they reach the pressure sensing sub-system.
  3. Simplify product design with an integrated approach.
  4. Speed time to market by not having to design an external filtering system.

Superior’s pressure sensors have an exceptionally low noise floor, which can make it possible to detect power line interference during measurements. However, with the inclusion of an integrated 50Hz/60Hz notch filter, this noise is effectively eliminated. As a result, users are able to maintain the advantage of using a pressure sensor with an ultra-low noise floor, without any external interference. Additionally, the seamless integration of the notch filter into the sensor module ensures that the interference caused by these frequencies is blocked out before it reaches the user’s application. With the notch filter already built into the sensor module, there is no longer any need for engineers to design and implement an external notch filter. As a result, this feature promotes greater system efficiency, reliability, and cost-effectiveness by removing the need for external filters.

Benefits of the integrated 50/60Hz Notch Filter include:

  1. Eliminate the noise from the power grid and AC devices before it reaches the sensing element
  2. Simplify product design with an integrated approach
  3. Speed time to market by not having to design and/or implement an external notch filter
  4. Lower overall system cost as an external notch filter is no longer required

A pressure switch is a mechanical or electronic device that is activated when a certain pressure threshold or set point is reached. These failsafe response components instruct the system to perform an action if a certain pressure threshold is met.

Types of Pressure Switches

Fixed Pressure Switches

As their name implies, fixed pressure switches have pre-set, non-changeable pressure thresholds that are set by the pressure switch manufacturer. The device maker receives the pressure switch already configured and cannot change values. Examples where fixed pressure switches are common are certain types of medical devices, such as ventilators.

Variable Pressure Switches

With variable pressure switches, the threshold value can be set either by the device maker or dynamically in the field. If it is controlled by the device maker, when they build their product they select certain resistor pairs that control the voltage input that determines the threshold. Once they build the product, the threshold value cannot be changed.

In cases where the threshold can be set in the field, this is typically done via software or a mechanical knob/switch. In this scenario, the pressure switch is usually not implemented as a safety feature. A good example is with air filters – where depending on the system implementation, the threshold value needs to be adjusted to account for any head loss in the flow stream.

Superior’s pressure switch changes state depending on the measured pressure being above or below a certain threshold. This can be used as a fast response failsafe feature for overpressure conditions, and to provide other simplified on/off system feedback. However, unlike other more common pressure switches, the Superior Sensor pressure switch includes three modes for setting threshold pressure, one fixed and two variable:

  • Fixed mode: Superior Sensor Technology sets the threshold and provides the ‘ready for use’ configured sensor (with integrated pressure switch) to the device manufacturer.
  • Variable mode 1: The device manufacturer can configure and set the proper thresholds at the time of product manufacturing.
  • Variable mode 2: Pressure thresholds are field programmable via software, so the pressure switch can be ‘tuned’ after product manufacture depending on the use case.

Benefits of Superior’s integrated pressure switch include:

  1. Flexibility with 3 modes of operation
  2. Lower system cost as the need for an external pressure switch is eliminated
  3. Smaller overall PCB footprint
  4. Improve the reliability of your product by eliminating external components
  5. Minimize system power and heat
  6. Simplify your product design
  7. Speed your time to market

With such a high demand for ventilators, it is critical that they continue to work without interruption. Eliminating failures before they become system alarms is a must. Implemented in close collaboration with partners, Superior’s proprietary Self Aware technology offers a capability that ensures maximum uptime and overall reliability.

Self Aware sensor technology tracks changes in error levels. By being part of a redundant system, the technology both eliminates a single point of failure service interruption and reduces false positives with respect to error notifications. Self Aware can reduce pressure sensor related alarm rates by up to 1000x.

NimbleSense Application Examples

CPAP/BiPAP: Advanced Digital Filtering, Closed Loop Control, Pressure Switch

Spirometry: Z-Track, Proprietary Zero-Noise Suppression

Ventilator: Advanced Digital Filtering, Pressure Switch, Self Aware

Air Quality: Advanced Digital Filtering, Closed Loop Control

HVAC DPT: Multi-Range, 50/60 Hz Notch Filter, Pressure Switch

Industrial: Advanced Digital Filtering, Multi-Range, 50/60 Hz Notch Filter, Pressure Switch

NimbleSense Benefits

  1. Industry leading performance with up to 10x improvement in Total Error Band (TEB) and accuracy
  2. Fully integrated sensor, ADC and DSP
  3. Optimized for specific end-user applications
  4. Simplifies the system architecture for the overall product
  5. Reduces design cycle time
  6. Lowers overall manufacturing and inventory costs
  7. Improves system reliability by integrating external functions and reducing component count
  8. Enables the faster development of product derivatives

Interested to learn more about the NimbleSense architecture?

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NimbleSense, Multi-Range, Z-Track and Self-Aware are trademarks of Superior Sensor Technology.