Based on Ohm's Law to determine the steady-state electrical parameters of the device testing methods, the DC test usually includes:

Short circuit - open (OPEN / SHORT): This test ensures that the normal test interfaces and devices to connect, contact the test by measuring the input and output pin protection diodes on the voltage drop to determine the natural connectivity. If applied on a suitable diode forward bias current, the voltage drop across the diode is about 0.7V,

Leakage parameters (INPUT LEAKAGE): under ideal conditions, can be considered input and three-state output pin to ground is open, but the actual situation, among them a high resistance state, the maximum current between them is called leakage current. Or separately as input tri-state output leakage current and leakage current, leakage current is generally due to the internal device and the insulation between the input pins oxide thin film in the production process caused by the formation of a similar case of short circuit, resulting in current through.

Output drive current (VOL, VOH, IOL, IOH). Output drive current test ensures that the device can maintain a certain predetermined load current output level, VOL and VOH specifications used to ensure that the device allows the device noise conditions can drive the input pins of multiple devices the ability to