Circuit switch for semi digital filtering

Abstract

The disclosed circuit switch includes following parts: current source in use for providing current for the circuit switch; being in use for controlling on / off of current, a pair of complementation switch is composed of a N type (or P type) metallic oxide semiconductor field effect tube (MOSEFT), and a P type (or N type) MOSEFT; being in use for converting current to voltage, and filtering signal, the transresistance amplifier is composed of a first capacitance, a resistance, and a operational amplifier; being in use for filtering out signal overshooting inducted by control signal, the lowpass filter is composed of a second capacitance and P type MOSEFT. Comparing with traditional circuit switch, the disclosed circuit switch can restrains signal overshoot more effectively. Features are: added capacitance does not require high linearity and is realizable by MOSEFT. Under deep submicro technique, MOSEFT can realize larger capacitance with smaller hardware cost.

Description

technical field [0001] The invention relates to a circuit switch for semi-digital filtering, which belongs to the technical field of electronic equipment. Background technique [0002] An existing semi-digital filter, published in "IEEE JSSC", vol.28, no.12, pp.1224-1233, Dec1993, A CMOS Oversampling D / A Converter with a Current-Mode SemidigitalReconstruction Filter, its The schematic diagram of the circuit is as figure 1 As shown, the transfer function of the filter is shown in formula (1): [0003] H ( z ) = Σ j = 0 N - 1 h ( j ) z - j - - - ( 1 ) [0004] The coeff...

AI Technical Summary

Problems solved by technology

Its disadvantage is that it requires a high degree of complementarity of control

Complementary signals in the chip are generated by inverters, and complementarity is difficult to guarantee

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