A linear, fully balanced, voltage-tunable CMOS operational transconductance amplifier (OTA) with large dc gain and wide bandwidth is described. The approach uses a twodifferential-pair transconductor with a cross-coupled input stage together with a negative resistance load for compensating the parasitic output resistance of the OTA. Since no additional internal nodes are generated, dc gain enhancement is obtained without bandwidth limitation. SPICE simulations show that total harmonic distortion at 1.42 V p -p is less than 1% with dynamic range equal to 66 dB at a power consumption of 2.7 mW from a single 5-V supply. As an example, the OTA is used to design a third-order elliptic lowpass filter in the very-high-frequency range, simulated in a standard 2 m CMOS process (MOSIS).The cutoff frequency of the filter is tunable in the range of 12-50 MHz.
Abstract. The architecture concept of a high-speed low-power analogue vision chip, which performs low-level real-time image algorithms is presented. The proof-of-concept prototype vision chip containing 32 × 32 photosensor array and 32 analogue processors is fabricated using a 0.35 µm CMOS technology. The prototype can be configured to register and process images with very high speed, reaching 2000 frames per second, or achieve very low power consumption, several µW. Finally, the experimental results are presented and discussed.
A high-frequency fully differential CMOS operational transconductance amplifier (OTA) is presented for continuous-time filter applications in the megahertz range. The proposed design technique combines a linear cross-coupled quad input stage with an enhanced folded-cascode circuit to increase the output resistance of the amplifier. SPICE simulations show that DC-gain enhancement can be obtained without significant bandwidth limitation. The two-input OTA developed is used in hgh-frequency tuneable filter design based on IFLF and LC ladder simulation structures. Simulated results of parameters and characteristics of the OTA and filters in a standard 1 . 2~ CMOS process (MOSIS) are presented. A tuning circuit is also discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.