Probe apparatus and method for measuring high-frequency signals.

摘要

A probe apparatus (1) comprises a probe contact (12) connected to a storage capacitance (17) via a photoconductive switch (16). The photoconductive switch (16) can be operated at high speed by means of a pulsed laser (20). The laser pulses (L) are synchronised with a moment in the operation cycle of the circuit (1) at which moment the voltage at the point under test (2) is to be measured. After a number of pulses and operation cycles the storage capacitance (17) is charged with the voltage value (V) to be measured. Then, the capacitance (17) does not form a load at the point under test (2) and the voltage (V) can be determined accurately. <IMAGE> <IMAGE>