• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.9
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• pp.74-80
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• 2009

This paper describes a $2{\sim}6GHz$ CMOS frequency synthesizer that employs only one LC-tank voltage controlled oscillator (VCO). For wide-band operation, optimized LO signal generator is used. The LC-tank VCO oscillating in $6{\sim}8GHz$ provides the required LO frequency by dividing and mixing the VCO output clocks appropriately. The frequency synthesizer is based on a fractional-N phase locked loop (PLL) employing third-order 1-1-1 MASH type sigma-delta modulator. Implemented in a $0.18{\mu}m$ CMOS technology, the frequency synthesizer occupies the area of $0.92mm^2$ with of-chip loop filter and consumes 36mW from a 1.8V supply. The PLL is completed in less than $8{\mu}s$. The phase noise is -110dBC/Hz at 1MHz offset from the carrier.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.190-196
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• 2010

Purpose: This study was undertaken to investigate the feasibility of using automated liquid-handling systems equipped with reusable fixed tips in Radioimmunoassays and to demonstrate that the use of an automated pipetting instrument can decrease in the typical daily workload. Materials and Methods: The precisions of the automated pipettor and the manual pipettor were determined gravimetrically (n=30). A total of 30 specimens for HBs Ag were repeatedly pipetted (three replicates) with the automated pipettor and then retested. PSA samples were simultaneously pipetted with either the automated pipettor or the manual pipettor and then analyzed (n=40). Sample carryover test assessed for CA19-9, AFP and HCG when the automated pipettor was used. Pipetting speed of the automated pipettor and the manual pipettor were compared by evaluation of each workload. Results: The precisions coefficients of variation (CV) were 2.1% for the automated pipettor and 1.6% for manual pipettor. The mean cpm and CV for each group of replicates were 41,203 cpm and 3.7% for HBs Ag positive specimens, and 99 cpm and 7.9% for HBs Ag negative specimens, respectively. PSA results showed no significant differences between automated pipettor and manual pipettor (p=0.15, r=0.999). Carryover for CA19-9, AFP and HCG analytes was <0.1 ppm or below the assay limit of detection. Pipetting speed was significantly improved by using the automated instrument. Conclusion: There was no evidence that the use of an automated pipettor adversely affected any of the performance characteristics of the assay. Indeed, routine use of the Tecan automated pipettor has resulted in a decrease in the typical daily workload.