UNTIL now the RF of a certain power was coupled into the pins of an IC to characterise its disturbance immunity. The IC's malfunction then indicated any internal interference.
This measuring method has now been refined thanks to the new Langer probes in the 500 series of the IC test system:
The RF disturbance from the power amplifier flows through the connected probe to the pin under examination. An RF current and voltage measurement is carried out in the probe tip at the same time.
Both the current and the voltage can be measured up to values of 3GHz and 30W. The probes have a coupling capacity of 3µF. The 501 probe can measure a maximum RF voltage of 50V effective and the 502 probe with pre-amplifier a voltage of 1V effective.
The parameters recorded allow more precise conclusions to be drawn with regard to an IC's EMC:
Functional faults that occur at large current values have magnetic causes; capacitive coupling will be the cause at large voltage values.
The reactive currents measured with the new measuring procedures are not detected by a common power measurement. Thus, detailed physical findings remained in the dark.
IC development benefits from this new measuring method of RF injection.