ISO 16525-2:2014 pdf free
ISO 16525-2:2014 pdf free.Adhesives一Test methods for isotropic electrically conductive adhesives
This part of ISO 16525 specifies test methods for isotropic electrically conductive adhesives used in wiring, die attach, and surface assembly of printed circuit boards of electronic devices. The test methods focus on volume and interfacial contact resistivity.
On the contact surface of the isotropic electrically conductive adhesives, a resistance component is present, which can be regarded as interfacial resistance. This might be so high that it cannot be neglected when compared with electrically volume resistivity of the isotropic electrically conductive adhesive.
This test provides a measurement, which measures this component only. This test is characterized by calculation of resistivity from a current passing through the test circuit and voltage.
Test apparatus, consisting of a current source and a voltage meter, both as specified in IEC 60468.
The potential difference is measured at the voltage terminals by applying a current to the printed circuit board using the current source from the current terminals in a specific direction. Figure 1 and Figure 2 show examples of configuration of the apparatus. A digital ohmmeter, which combines all these devices, may be used as an alternative.
It is preferable to use a dry circuit-type apparatus because it does not affect the irreversibility of conductivity of the interface of the isotropic electrically conductive adhesive. For measurement of interfacial resistance, it is preferable to use a multichannel ohmmeter because it is necessary to switch from one pair of terminals to the other and the lengths of the wires differs.
Resistance is obtained from the voltage drop when a constant current is applied. Therefore, set a current value so that voltage resolution can be sufficiently small compared to the measured voltage. In the unlikely event that the specimen generates heat because an excessively high current occurs, reduce the current value and shorten the period for each measurement session. Usually, a maximum current is recommended to be approximately 10 mA. ISO 16525-2 pdf download.
