ETRI Journal

Electronics and Telecommunications Research Institute (한국전자통신연구원)
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Switched-Capacitor Variable Gain Amplifier with Operational Amplifier Preset Technique

  • Cho, Young-Kyun (Convergence Components & Materials Research Laboratory, ETRI) ;
  • Jeon, Young-Deuk (Convergence Components & Materials Research Laboratory, ETRI) ;
  • Kwon, Jong-Kee (Convergence Components & Materials Research Laboratory, ETRI)
  • Received : 2008.09.19
  • Accepted : 2009.02.18
  • Published : 2009.04.30
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Abstract

We present a novel operational amplifier preset technique for a switched-capacitor circuit to reduce the acquisition time by improving the slewing. The acquisition time of a variable gain amplifier (VGA) using the proposed technique is reduced by 30% compared with a conventional one; therefore, the power consumption of the VGA is decreased. For additional power reduction, a programmable capacitor array scheme is used in the VGA. In the 0.13 ${\mu}m$ CMOS process, the VGA, which consists of three-stages, occupies 0.33 $mm^2$ and dissipates 19.2 mW at 60 MHz with a supply voltage of 1.2 V. The gain range is 36.03 dB, which is controlled by a 10-bit control word with a gain error of ${\pm}0.68$ LSB.

Keywords

References

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