4. The electrically programmable load according to claim 1 , wherein each of said each load unit elements comprises two voltage dependent capacitors.
1. An electrically programmable load having an impedance value dependent on a received control word, the electrically programmable load comprising a plurality of parallel load units, each load unit comprising at least one load unit element, each load unit element being arranged to receive a control word component of said control word and having a load unit element impedance value which depends on a control word component value of said control word component, wherein said control word component value is one of three or more different biasing values.