An ultra low-power class-AB sinh integrator

ABSTRACT

A new ultra low-power Class-AB Sinh integrator is proposed here. The translinear companding integrator is based on hyperbolic-sine transconductors and uses only one grounded capacitor to implement a Class-AB integrator, which saves considerable chip area. Furthermore, the proposed circuit presents excellent performance with respect to power efficiency. To validate the circuit principle, the integrator has been simulated in standard 35 μm CMOS technology and designed to operate from a 1.5-V (± 0.75V) supply voltage, with a current consumption of only 14nA. The THD is kept below 1%, with a modulation index as high as 20 and yields a 75-dB dynamic range at the 1-dB compression point.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: Advanced technologies

Additional Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: Input/output circuits

General Terms:
Design, Documentation, Performance, Theory, Verification

Keywords:
Sinh integrator, analog electronics, class-AB integrator, log-domain filters, low-power circuit design