US Patent 7109785 Current source for generating a constant reference current

Current source for generating a constant reference current having an amplifier circuit, which outputs a negative feedback voltage, present across a first resistor, in inverted amplified fashion as amplification output voltage; a first voltage/current converter, which generates a current in a manner dependent on the amplifier output voltage; a first current mirror circuit, which mirrors the current generated by the voltage/current converter to form a mirrored current which flows through the first resistor in order to generate the negative feedback voltage; and having a second current mirror circuit, which mirrors the current generated by the voltage/current converter to form the reference current.