Reliability of Operating Electronic equipments on board of artificial satellites, spacecrafts, and military aircraft's in extreme environment require radiation hardening. The effects of radiation, both single event and total ionization dose on the phase frequency detector, voltage controlled oscillator, charge pump and filters for PLL application are studied. The focus is on and CMOS based technologies; however, other high performance technologies will be discussed wherever appropriate. The points of concern are single event effects (SEE) and steady state total ionizing dose (TID) IC...