A Reconfigurable Differential-to-Single-Ended Autonomous Current Adaptation Buffer Amplifier Suitable for Biomedical Applications
Journal
IEEE Transactions on Biomedical Circuits and Systems
Date Issued
2021
Author(s)
Abstract
A reconfigurable differential-to-single-ended autonomous current adaptation buffer amplifier (ACABA) suitable for biomedical applications is proposed. The ACABA, based on floating-gate technologies, is a capacitive circuit, of which output DC level and bandwidth can be adjusted by programming charges on floating nodes. The gain is variable by switching different amounts of capacitors without altering the output DC level. Without extra sensing and control circuitries, the current consumption of the proposed ACABA increases spontaneously when the input signal is fast or large, achieving a high slew rate. The supply current dwindles back to the low quiescent level autonomously when the output voltage reaches equilibrium. Therefore, the proposed ACABA is power-efficient and suitable for processing physiological signals. A prototype ACABA has been designed and fabricated in a 0.35m CMOS process occupying an area of 0.151 mm2. When loaded by a 10 pF capacitor, it consumes 3 W to achieve a unity-gain bandwidth of 100 kHz with a measured IIP2 value of 52.66 dBV and a slew rate of 7.86 V/s. IEEE
Subjects
Biomedical monitoring
buffer amplifier
capacitive circuit
Capacitors
class-AB amplifier
current adaptation
Differential-to-single-ended
Electrocardiography
floating-gate transistor
Linearity
low-power circuit
Programming
Sensors
Transistors
variable gain amplifier
Bandwidth
Capacitive sensors
Differential amplifiers
Electric power utilization
Low power electronics
Medical applications
Power amplifiers
Timing circuits
Variable gain amplifiers
Voltage regulators
'current
Capacitive circuits
Class-AB amplifiers
Current adaptation
Differential to single-ended
Floating gate transistors
Low-power circuit
Analog circuits
Type
journal article