Input Impedance Chopper Stabilized Amplifier with Dual Feedback Loops Input Impedance Technique 3 Architecture CCIA(Capacitively-coupled Chopper Instrumental Amplifier) core with RRL(Ripple Reduction Loop) & SS-DSL(Single-slope-assisted DC-servo Loop) PGA and 10b SAR ADC DPFL(Dual Positive Feedback Loops) for impedance boosting Signal generator and automatic calibration logic for external parasitics adaptation Characteristics Verified IP CCIA(Capacitively-coupled Chopper Instrumental… Continue reading Technique III: Input Impedance Chopper Stabilized Amplifier with Dual Positive Feedback Loops

Parasitic Insensitive Impedance Boosting with 4-tap FIR Impedance Boosting Technique 2 Architecture CTDSM using low noise linear integrator & VCO-based quantizer Parasitic insensitive impedance boosting with 4-tap FIR Current recycling OPAMP and chopper stabilization for integrator noise reduction VCO based quantizer and 2nd order noise shaping for quantization noise reduction Block Diagram Performance – SNDR,… Continue reading Technique II: Parasitic Intensive Impedance Boosting with 4-tap FIR

Impedance Boosting with Additional Amplifier Impedance Boosting Technique I Architecture Truncation error shaping using the NS-SAR ADC 1st-order DT DSM with CDS integrator and 2nd-order NS SAR quantizer Performance – SNDR, IRN SNDR(Signal to Noise/Distortion Ratio) : 94.5dB at 500Hz BW IRN(Input Referred Noise) : 0.174 µV/√Hz Back to Technology

ExG Biosignal Acquisition Low Power, Low Noise, High CMRR, High Input Impedance and Wide Input Range Challenges Low power consumption : <10 μW Low noise : <1 μVrms Large input swing : >200 mVPP Wide dynamic range : >90 dB High CMRR : >70 dB High input impedance : >100 MΩ Obstacles in ExG Biosignal… Continue reading ExG Biosignal Acquisition

Neurotherapeutics Wide Dynamic Range and Low Input-referred Noise IC Challenges Stimulation Artifact Motion Artifact Circuit Noise Solution – Adaptive Amplifier Gain & ADC Resolution Control Low Amplitude Signal -> High Gain & Low DR High Amplitude Signal -> Low Gain & High DR Increased Dynamic Range with Auto-ranging & AGC Power efficient digital conversion with… Continue reading Neurotherapeutics

CM Charge Pumping Stable and Simple Circuit Structure and Operation CM signal sensed at the input of the front-end LNA If the CM signal exceeds the desired CM range, the displacement current from the CM input absorbed by a CMCP Input swing kept within the desired CM range, even in the presence of excessively large… Continue reading CM Charge Pumping