CAPACITOR CHARGING CIRCUIT WITH LOW SUB-THRESHOLD TRANSISTOR LEAKAGE CURRENT

摘要

A capacitor charging circuit has input, output and control nodes, first and second series connected primary FETs, and first and second leakage current reduction FETs. All of the FETs have their gates coupled to the control node. The first primary FET is coupled between the input and output nodes, and the second primary FET is coupled between the output node and a leakage current reduction node. The first leakage current reduction FET is coupled between a supply line and the leakage current reduction node, and the second leakage current reduction FET is coupled between the leakage current reduction node and ground. When a control signal at the control node is low, the first primary FET and the first leakage current reduction FET are conductive, and the second primary FET and the second leakage current reduction FET are non-conductive, which eliminates sub-threshold leakage current flowing through the second primary FET.

主权项

1. A capacitor charging circuit with reduced sub-threshold transistor leakage current, the circuit comprising:
an input node; an output node; a control node; first and second series connected primary field effect transistors, each of the primary transistors having a gate electrode coupled to the control node, and wherein the first primary transistor is coupled between the input node and the output node and the second primary transistor is coupled between the output node and a leakage current reduction node; first and second series connected leakage current reduction field effect transistors, each of the leakage current reduction transistors having a gate electrode coupled to the control node, and wherein the first leakage current reduction transistor is coupled between a power supply line and the leakage current reduction node and the second leakage current reduction transistor is coupled between the leakage current reduction node and a ground line, wherein, in operation, when a control signal at the control node is at a first voltage level, the first primary transistor and the first leakage current reduction transistor are in a conductive state and the second primary transistor and the second leakage current reduction transistor are in a non-conductive state.