An electronic circuit (103, fig. 21) comprising: an input terminal; an output terminal; a first supply rail; a second supply rail; a first field effect transistor, FET, of a first type and having respective gate, source and drain terminals; a second FET of said first type and having respective gate, source and drain terminals; a third FET of said first type and having respective gate, source and drain terminals; and a fourth FET of said first type and having respective gate, source and drain terminals, wherein the source of the first FET is connected to the first supply rail, the drain of the first FET and the source of the second FET are connected to the output terminal, the drain of the second FET is connected to the second supply rail, the gate of the third FET and the gate of the fourth FET are connected to the input terminal, and the drain of the third FET is connected to the second supply rail, characterised in that the electronic circuit further comprises a first load resistor and a second load resistor, the first load resistor is connected between the first supply rail and the source of the third FET, the second load resistor is connected between the drain of the fourth FET and the second supply rail, the gate of the second FET is connected to a node between the source of the third FET and the first load resistor such that a voltage at the source of the third FET is applied to the gate of the second FET, and the gate of the first FET is connected to a node between the drain of the fourth FET and the second load resistor such that a voltage at the drain of the fourth FET is applied to the gate of the first FET. an input terminal; an output terminal; a first supply rail; a second supply rail; a first field effect transistor, FET, of a first type and having respective gate, source and drain terminals; a second FET of said first type and having respective gate, source and drain terminals; a third FET of said first type and having respective gate, source and drain terminals; and a fourth FET of said first type and having respective gate, source and drain terminals, wherein the source of the first FET is connected to the first supply rail, the drain of the first FET and the source of the second FET are connected to the output terminal, the drain of the second FET is connected to the second supply rail, the gate of the third FET and the gate of the fourth FET are connected to the input terminal, and the drain of the third FET is connected to the second supply rail, characterised in that the electronic circuit further comprises a first load resistor and a second load resistor, the first load resistor is connected between the first supply rail and the source of the third FET, the second load resistor is connected between the drain of the fourth FET and the second supply rail, the gate of the second FET is connected to a node between the source of the third FET and the first load resistor such that a voltage at the source of the third FET is applied to the gate of the second FET, and the gate of the first FET is connected to a node between the drain of the fourth FET and the second load resistor such that a voltage at the drain of the fourth FET is applied to the gate of the first FET.