Chutham Sawigun

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—In order to realize a nano-power wavelet filter for biomedical applications, this paper applies the Singular Value Decomposition approximation to transform the time domain 1 st-derivative of a Gaussian (gauss1) wavelet base into a 5 th-order z-domain transfer function. Consequently, to realize the approximated transfer function in CMOS technology employing(More)
— According to recent physiological experiments, the envelope and phase of speech signals are required to enhance the perceptive capability of a cochlear implant processor. In this paper, the design of an analog complex gammatone filter is introduced in order to extract both envelope and phase information of the incoming speech signals as well as to emulate(More)
— A nano-power 4 th-order band-pass filter operating from a 0.5 V supply voltage with an adjustable center frequency, ranging from 250 Hz to 4 kHz (4 octaves), is presented. The filter is constituted from cascadable 2 nd-order circuit cells that are realized by a network of three transistors and two capacitors comprising only one branch of bias current. As(More)
—This paper proposes the design of a current-mode sample and hold circuit using subthreshold MOSFETs. The proposed circuit combines negative feedback and the compressive characteristic of a class-AB weak inversion transconductor to achieve low switching error, high signal-to-noise ratio and high dynamic range from a low supply voltage and very low current(More)
—Real time action potential (AP) detection is an important requirement for development of fully implantable neuroprosthetic devices. We present an ultra low-power CMOS analog circuit for detection of APs embedded in a noisy signal. The proposed strategy isolates APs by detecting subsequently a positive and a negative spike of each AP. An AP is detected only(More)
— An ultra low-power class-AB four-quadrant current multiplier designed to be used in an energy-based action potential detector is presented. The multiplier is considered the first topology that provides fully class-AB operation. The topology is constituted by a class-AB current amplifier and a current splitter which can handle input signals in excess of(More)
Keywords: Analog filter Bandpass filter Bionic ear processor Biomedical circuit CMOS circuit G m –C filter Low voltage Ultra low-power a b s t r a c t A compact nano-power fourth-order bandpass filter operating from a 0.5 V supply, with an adjustable center frequency ranging from 125 Hz to 16 kHz, is presented. The filter is constituted from cascadable(More)