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Haider M.R.,Sonoma State University | Islam S.K.,University of Tennessee at Knoxville | Mostafa S.,University of Tennessee at Knoxville | Zhang M.,Technology Group Co. | Oh T.,TLI Inc.
IEEE Transactions on Biomedical Circuits and Systems | Year: 2010

Low voltage and low power are two key requirements for on-chip realization of wireless power and data telemetry for applications in biomedical sensor instrumentation. Batteryless operation and wireless telemetry facilitate robust, reliable, and longer lifetime of the implant unit. As an ongoing research work, this paper demonstrates a low-power low-voltage sensor readout circuit which could be easily powered up with an inductive link. This paper presents two versions of readout circuits that have been designed and fabricated in bulk complementary metaloxide semiconductor (CMOS) processes. Either version can detect a sensor current in the range of 0.2 μA to 2 μA and generate square-wave data signal whose frequency is proportional to the sensor current. The first version of the circuit is fabricated in a 0.35-μm CMOS process and it can generate an amplitude-shift-keying (ASK) signal while consuming 400 μW of power with a 1.5-V power supply. Measurement results indicate that the ASK chip generates 76 Hz to 500 Hz frequency of a square-wave data signal for the specified sensor current range. The second version of the readout circuit is fabricated in a 0.5-μm CMOS process and produces a frequency-shift-keying (FSK) signal while consuming 1.675 mW of power with a 2.5-V power supply. The generated data frequency from the FSK chip is 1 kHz and 9 kHz for the lowest and the highest sensor currents, respectively. Measurement results confirm the functionalities of both prototype schemes. The prototype circuit has potential applications in the monitoring of blood glucose level, lactate in the bloodstream, and pH or oxygen in a physiological system/environment. © 2010 IEEE.

Gil J.,RadioPulse | Gil J.,TLI Inc. | Kim J.-H.,RadioPulse | Kim C.S.,RadioPulse | And 12 more authors.
IEEE Transactions on Microwave Theory and Techniques | Year: 2014

A fully integrated low-power high-coexistence 2.4-GHz ZigBee transceiver implemented in 90-nm CMOS technology is demonstrated. The two-point direct-modulation with a fractional-N synthesizer is adopted in the transmitter architecture. The transmitter can provide high output power of + 9 dBm and excellent error vector magnitude of 5.1%. The direct conversion is used in receiver for simplicity and-97-dBm minimum receiver sensitivity is achieved. Current consumptions for a TX at + 9-dBm output power and for an RX are 28.4 and 15.4 mA, respectively. Excellent coexistence is presented through wireless local area network interferer rejection performance. © 2014 IEEE.

A flat panel display device and a source driver circuit for the flat panel display device are provided for performing multiple driving operations within a unit sourcing period. In the flat panel display device, multiple driving operations are performed within the unit sourcing period, and source voltages are supplied to a selected number of data lines in each driving operation. In this case, one DAC is driven to generate source voltages for a plurality of data lines. In the flat panel display device, the number of the DACs is reduced and the overall layout area is greatly reduced. Also, standby power consumption can be greatly reduced due to the reduced number of amplifiers. Since the source voltages provided by the same amplifier are provided to adjacent data lines, a metal layer can be easily wired in the display panel.

A differential data transferring system and method uses three level voltages to simultaneously transfer three signals (for example, two data signals and one clock signal) across two transfer line sets (i.e., four transfer lines). Therefore, the differential data transferring method increases transferring efficiency by using fewer transfer lines. Also, according to the differential data transferring system and method, one of two transfer lines forming a transfer line set is controlled to a middle voltage level, while the other transfer line is controlled to either a high voltage or a low voltage. Accordingly, the voltage difference between the two transfer lines may be maintained at a constant amplitude. Additionally, the difference between first and second dividing voltages DC

Disclosed is a light emitting diode (LED) illuminating apparatus having enhanced stability of the quantity of light. The LED illuminating apparatus includes an LED lighting block connected to a rectified voltage and including at least one LED module, an alternative reference voltage generating block configured to detect the rectified voltage and generate an alternative reference voltage, and a switching block connected to the tap and configured to form a closed circuit including the at least one LED module. The at least one LED module includes a cathode terminal having a tap. The alternative reference voltage has a voltage level according to a root mean square (RMS) value of the rectified voltage. The amount of currents flowing through the closed circuit is controlled by the alternative reference voltage to have a negative relationship with the RMS value of the rectified voltage. In an LED illuminating apparatus according to the present invention, degradation in uniformity of light due to instability of an input power is reduced.

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