Low power wireless medical electronic design is a heated research topic due to the development of remote medical diagnosis systems and long-term treatment assistances. In general, such medical devices contain bio-signal sensor that monitor the health status of a patient or health-conscious person. Our main goal is to design an LNA that is suitable for amplifying bio-signals in low-power remote sensing devices. In this work, the business strategy and the IP strategy is being studied and presented. Ring-amplification technique is a novel amplifier design approach, which has the potential to achieve high gain with minimal power dissipation. The motif behind applying ring-amplification technique to low-power LNA design is that ring-amplifier has the potential to achieve high gain with low power dissipation as well as a relatively simple structure. This work reviews the current status of ring-amplifier design, as well as explores the ring-amplifier design process. The original ring-amplifier approach is not suitable for low-noise amplifier design due to its single-ended structure, therefore effort is being made to modify the ring-amplifier structure to make the amplifier suitable for employing flicker noise cancellation techniques. The eventual result of this work, the differential input ring-amplifier employing chopper stabilization, which achieved closed-loop gain of 63.93dB, THD -78dB, UGB of 12MHz and a positive phase margin which indicates the stability of the ring-amplifier. At 10Hz the output noise voltage density is 120uV/(Hz)1/2, which is approximately an order of magnitude noise reduction at low frequencies, compared to the simple ring-amplifier.




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