A constant current source for generating a constant reference current that is relatively temperature insensitive. The constant current source comprises: i) first circuitry for generating a first output current that increases with increases in temperature; ii) second circuitry for generating a second output current that decreases with increases in temperature; and iii) a current combiner circuit that combines the first and second output currents to thereby generate the constant reference current. A change in the first output current caused by a temperature change is at least partially offset by a change in the second output current caused by the temperature change.