| 摘要 |
PURPOSE:To simultaneously make possible the test of a plurality of IC elements of input and output pins with the use of a comparatively small-scale hardware. CONSTITUTION:The output sides of a driver 21 are connected to the input and output pins corresponding to IC elements 121-12n to be tested through loads 221-22n and these input and output pins are coupled to the input sides of comparators 131-13n respectively. In a condition in which data IOD given to the driver 21 indicates input, the driver 21 outputs either VH or VL, a third level VT in the intermediate of VH and VL is output in the condition in which the data IOD indicates output. When the output from the input and output pins is normal, VT is selected so that normal current may be allowed to flow in a load 22. |
