Skip to main content
Industrial Research And Consultancy Centre
Patent
High EMI Immune Transconductance-Capacitance Low Pass Filter
Abstract

This invention is a specialized electronic filter designed to reduce DC offset caused by high-frequency electromagnetic interference (EMI) in circuits. It features a voltage attenuator, a main trans-conductor, and a feedback loop to enhance performance. The voltage attenuator uses a complex arrangement of three differential pairs of transistors and high-pass filters to precisely manage signal processing, allowing low-frequency signals to pass through while blocking high-frequency noise. A load capacitor is also included to stabilize the output, ensuring cleaner and more reliable circuit performance.

Societal Impact

This technology improves medical devices by filtering out unwanted noise, leading to more accurate readings. This enhancement in accuracy improves patient care, enabling better health monitoring and diagnostics, ultimately benefiting society by promoting healthier lives and more effective medical treatments.

Salient technical features and Advantages of the Technology
  • DC Offset Reduction: Uniquely targets and mitigates DC offset caused by out-of-band EMI frequencies. Voltage Attenuator: Features a source buffered differential pair structure that attenuates the input signal. 
  • Differential Transistor Pairs: Utilizes three differential pairs of transistors arranged in a specific configuration to improve filtering. 
  • High-Pass Filters: Includes high-pass RC filters with a cut-off frequency of 10 MHz to manage high-frequency noise. 
  • GM cell: It features an enhanced source-buffered structure, delivering superior performance over previous designs.


  • DC Offset Reduction: Uniquely targets and mitigates DC offset caused by out-of-band EMI frequencies. Voltage Attenuator: Features a source buffered differential pair structure that attenuates the input signal. 
  • Differential Transistor Pairs: Utilizes three differential pairs of transistors arranged in a specific configuration to improve filtering. 
  • High-Pass Filters: Includes high-pass RC filters with a cut-off frequency of 10 MHz to manage high-frequency noise. 
  • GM cell: It features an enhanced source-buffered structure, delivering superior performance over previous designs.
Technology readiness level

3

Current Status of Technology

The novel circuit has achieved a filter cutoff in the range of tens of Hz, ideal for biomedical applications. It successfully eliminates in-band DC offset caused by EMI, enhancing signal accuracy and reliability.

Relevant Industries

telecommunication, electronics, automotive, medical devices, aerospace and defense, industrial machinery

Applications or Domain

This technology targets biomedical applications, specifically aiming for a filter cutoff in the range of tens of Hz. It addresses the issue of in-band DC offset caused by EMI, a problem thoroughly analyzed and resolved in our design. By improving the filter design to eliminate this offset, our work ensures more accurate and reliable biomedical signal processing, crucial for effective health monitoring and diagnostics.