Methods to provide and expose a diagnostic connector on overmolded electronic packages
View Patent ↗An overmolded electronic assembly is provided having a circuit board with electronic devices and a diagnostic connection. The diagnostic connection includes electrical conductors having a distal end projecting above a first side of the circuit board, for example, circuit pads having solder thereon or conductive pins oriented substantially perpendicular to the circuit board. The electrical conductors are overmolded with sealing material along with the other electronic devices and circuit board area. The encapsulation or sealing material overlying the electrical conductors is removed from the outside surface down to at least the distal end of the electrical conductors. The sealing material may be removed, for example, by mechanical cutting, laser cutting, or high pressure jet erosion, for example, by a high pressure water or liquid nitrogen stream.
1. A method of providing a diagnostic connection for an over-molded electronic package including a circuit board and an electronic component mounted on the circuit board, comprising the steps of:
forming electrical conductors on a first side of the circuit board laterally displaced from said electronic component, the electrical conductors having distal ends projecting above the first side of the circuit board;
over-molding the circuit board, the electronic component and the electrical conductors with an encapsulating material; and
selectively removing a portion of the encapsulating material that overlies said electrical conductors without disturbing other portions of the encapsulating material to form a cavity in the encapsulating material with the distal ends of the electrical conductors being exposed at a floor of the cavity for access to a diagnostic probe inserted into said cavity.
2. The method of claim 1 , including the steps of:
dispensing a sealing material onto said electrical conductors before over-molding the circuit board, the electronic component and the electrical conductors with said encapsulating material; and
first removing the portion of the encapsulating material that overlies said electrical conductors and then removing a portion of the sealing material that overlies said electrical conductors to form said cavity.
3. A method of providing a diagnostic connection for an over-molded electronic package including a circuit board and an electronic component mounted on the circuit board, comprising the steps of:
forming electrical conductors on a first side of the circuit board laterally displaced from said electronic component, the electrical conductors having distal ends projecting above the first side of the circuit board;
providing a protective box having an open end, and securing said box to said circuit board about said electrical conductors with said open end facing said circuit board so as to define a closed volume of air overlying said electrical conductors;
over-molding at least the circuit board and the electronic component with an encapsulating material; and
removing a wall of said protective box that overlies said electrical conductors to expose the closed volume of air overlying said electrical conductors to thereby form said a cavity in the encapsulating material with the distal ends of the electrical conductors being exposed at a floor of the cavity for access to a diagnostic probe inserted into said cavity.
4. The method of claim 3 including the steps of:
over-molding the circuit board, the protective box, and the electronic component with said encapsulating material; and
first removing a portion of the encapsulating material that overlies said electrical conductors and then removing the wall of said protective box that overlies said electrical conductors.