A Very High-Frequency Transistor-Only Linear Tunable Companding Current-Mode Integrator

  • Apisak Worapishet
  • Jirayuth Mahattanakul
  • Chris Toumazou
Part of the The Springer International Series in Engineering and Computer Science book series (SECS, volume 550)


A low-distortion tunable transistor-only integrator suitable for applications in the frequency range approaching the f T of transistors is presented. The circuit is a modified version of the recently introduced companding current-mode integrator utilizing the non-linear base-emitter diffusion capacitance of the BJT. A first-order approximation of the circuit characteristics is explained, followed by a brief discussion on the departure from ideal characteristics due to transistor nonidealities. Experimental and simulated results of practical integrators are given to verify the feasibility of the proposed modified circuit.


Collector Current Analog Integrate Circuit Base Terminal Unity Gain Frequency Balance Voltage 
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Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • Apisak Worapishet
    • 1
  • Jirayuth Mahattanakul
    • 2
  • Chris Toumazou
    • 3
  1. 1.Department of Telecommunication EngineeringMahanakorn University of TechnologyBangkokThailand
  2. 2.Department of Electronic EngineeringMahanakorn University of TechnologyBangkokThailand
  3. 3.Technology and MedicineImperial College of ScienceLondonUK

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