For integrated circuit ESD protection design, it is important to know what kind of I-V characteristics and how much current flow can be allowed against constant short-period pulse waves resembling ESD surge on protection elements and protected elements.
Although conventional DC measurement may make likely thermal destruction, measurement with a TLP device makes it possible to analyze and obtain characteristics for high currents up to 10A, with small risk of thermal destruction.
Further, TLP measurement to a real integrated circuit not only contributes to ESD protection design, but can also be employed as a tool for analyzing failure as a result of ESD. Also, test objects are not limited to IC wafers and bare chips, but also widely include packaged devices and board modules.
We at OKI Engineering provide accurate ESD characteristics and parameters (for good ESD-Event) with TDR (Time-Domain-Reflection) TLP measurements.
During TDR-TLP measurement, rectangular waves are applied to the device under test (DUT), then, by analysis of the reflection waves from the DUT observed with an oscilloscope, the operation characterisctics of the device at ESD-Event are obtained.
Configuration of TLP Measurement Equipment
The rectangular wave applied to the device under test (DUT) stores electrical charge in the pulse generator's coaxial cable and is shaped by switching the transmission path on the DUT side. This rectangular wave is applied to the DUT through the transmission path after controlling the waveform's rise via a filter.
Then, voltage and current shapes of the incident wave are observed with an oscilloscope in between the DUT pulse generator's waveform monitoring section.
In case of impedance mismatching between the DUT and transmission path, the energy which cannot be consumed by the DUT passes as reflection wave through the waveform monitoring section.
Incident and reflection waves are combined and observed with an oscilloscope at the waveform monitoring section, however, the combined portion is observed as a transient phenomena of the DUT.
The average value of this combined portion of the waveform is plotted as a I/V curve and extracted as ESD-Event operating characteristics of the device.
TLP Measurement Result