Patent ID: 8400080

Claim:
A tunable current source, comprising: a voltage dependent current source arranged to provide a current I c ; a voltage source connected to the voltage dependent current source; and a multiprocessor control unit (MCU) comprising: an input node connected to the voltage source arranged to receive a sense voltage, an output node in communication with a control node of the voltage dependent current source, and a logic circuit coupled to the input node and the output node, wherein logical processing carried out by the logic circuit results in a control signal at the control node of the voltage dependent current source, the logical processing in accordance with a fixed pre-determined relationship between the sense voltage received at the input node and a range of sense voltage values, the control signal causing the voltage dependent current source to provide the current I c , wherein when the sense voltage is changed by ±ΔV, the current I c provided by the voltage dependent current source changes in direct proportion to ±ΔV.