Low power voltage reference

A circuit portion for generating an output reference voltage, the circuit portion comprising:

• a self-cascode circuit portion arranged to generate a first intermediate reference voltage at a first node based on an input current provided thereto;
• a follower circuit portion arranged to mirror the input current and to generate a second intermediate reference voltage at a second node based on the first intermediate reference voltage;
• and
• a reference resistor coupled to the second node;
• wherein:
• the follower circuit portion comprises a feedback loop arranged to counteract variations in the second intermediate reference voltage;
• and
• the circuit portion is arranged to generate the output reference voltage based on a current through the reference resistor,
• wherein the self-cascode circuit portion comprises a cascode transistor and a main transistor, and the gate terminal of the main transistor is coupled to the gate terminal of the cascode transistor.