Patent ID: 8816891

Claim:
A wide range input current circuitry for an analog to digital converter (ADC), the wide range input current circuitry comprising: a port for receiving an input current; a control circuitry; a first resistor having a first resistance; a first electronically controlled switch arranged to couple, responsive to said control circuitry, said port to said first resistor so as to provide a first current path for a first portion of the received input current, said first electronically controlled switch having a first area; a second resistor having a second resistance, said second resistor coupled to the input of the ADC; and a second electronically controlled switch arranged to couple said port to said second resistor so as to provide a second current path for a second portion of the received input current, said second electronically controlled switch having a second area, wherein the ratio between the first area and the second area is equal to the ratio between the second resistance and the first resistance, wherein said control circuitry is arranged to operate in a high current mode in the event that the input current exhibits an intensity within a first predetermined range and is arranged to operate in a low current mode in the event that the input current exhibits an intensity within a second predetermined range, said second predetermined range lower than the first predetermined range, wherein in said high current mode said control circuitry is arranged to close said first electronically controlled switch so as to couple said port to said first resistor and thereby provide the first current path for the first portion of the received input current, and wherein in said low current mode said control circuitry is arranged to open said first electronically controlled switch, said first electronically controlled switch arranged when opened to prevent the flow of the first portion of the received input current through said first resistor.