LOW PROFILE, CURRENT-DRIVEN RELAY FOR INTEGRATED CIRCUIT TESTER

摘要

A relay (70) includes contacts (73) residing within a glass tube (72). A coil (76) surrounding the tube (72) and a switch (66) are connected in parallel between two terminals (77) of the relay (70). A current source supplies a current to the coil (76) and switch (66). When the switch (66) is open, substantially all of the current passes through the coil (76) and the coil (76) produces a sufficient amount of magnetic flux to close the relay's contacts (73). When the switch (66) closes, it shunts a sufficient amount of the current away from the coil (76) to reduce the magnetic flux it produces below the level needed to keep the contacts (73) closed. The current source is sized so that the coil (76) requires relatively few turns, thereby allowing the relay (70) to be relatively thin. The coil (76) is formed by a conductor (140) embedded in an insulating substrate (128) surrounding the tube (72).