| 摘要 |
<p>A system and method for unambiguously determining the orientation of a semiconductor component (48,50,52) in a circuit. The invention draws a predetermined biasing current from the signal node (74,80) of a circuit that is sufficient to forward bias protection (28) and/or parasitic (32) diodes that exist between the ground pin (62,64,66) and signal pin (46,70,72,76,78,82) of the semiconductor component (48,50,52). Hence, if all of the semiconductors coupled to a signal node are connected in proper orientation, a voltage of -VD will be detected on the signal node (74,80). A voltage of approximately two diode voltage drops is applied to the power node so that the protection (28) and/or parasitic (32) diodes of a semiconductor (48,50,52) placed in the circuit in reverse orientation will be forward biased to produce a voltage on the signal node (74,80) equal to approximately one diode voltage drop. Missing components and bent pins do not affect the results of the test performed by the present invention. Guarding techniques on the signal node are not required since impedances coupled to the signal node (74,80) are normally high enough to allow the protection (28) and/or parasitic (32) diodes to be forward biased by current supplied by the current source (84,86).</p> |
