Low-noise reference voltages distribution circuit

摘要

A low-noise reference voltages distribution circuit has a multi-output voltage-to-current converter configured to receive an input reference voltage and to provide a plurality of output reference currents to be converted into a plurality of local reference voltages by corresponding receiving circuits. The converter includes an input section, an output section and a low-pass filter. The input section generates a reference current based on the input reference voltage, and has a current mirror input transistor having a voltage controlled input terminal. The output section includes a plurality of current mirror output transistors outputting reference currents to the plurality of reference currents, respectively, and having a voltage controlled input terminal connected to a common input node. The low-pass filter has an input node connected to the voltage controlled input terminal of the current mirror input transistor and an output node connected to the common input node.

主权项

1. A reference voltages distribution circuit comprising:
a multi-output voltage to current converter configured to receive an input reference voltage and to provide a plurality of output reference currents to be converted into a plurality of local reference voltages at corresponding receiving circuits connected to said reference voltages distribution circuit, the multi-output voltage to current converter including: an input section configured to generate a reference current based on the input reference voltage, the input section comprising a current mirror input transistor having a voltage controlled input terminal; an output section having
a plurality of current mirror output transistors each configured to provide a corresponding output reference current of the plurality of output reference currents, anda common input node to which voltage controlled input terminals of the current mirror output transistors are respectively connected; and a low-pass filter having an input node connected to the voltage controlled input terminal of the current mirror input transistor, and an output node connected to the common input node of the output section, said low pass filter including:
a first MOS transistor having a first terminal connected to the input node of the low-pass-filter, a second terminal connected to the output node of the low-pass filter, and a gate terminal; anda biasing circuit of said first MOS transistor configured to apply a DC control voltage to said gate terminal of the first MOS transistor such that the first MOS transistor operates in a weak inversion or a sub-threshold region, wherein said control voltage causes a desired resistance value R between said first terminal and said second terminal of the first MOS transistor.