Section 3: Equipment startup
S535 Wafer Acceptance Test System Administrative Guide
3-10
S535-924-01 Rev. B / January 2019
For additional information about the 9139A-PCA and 9139B-PCA, see the
9139A-PCA Probe Card
Adapter Instruction Manual
(part number 9139A-901-01) and
9139B-PCA Probe Card Adapter
Instruction Manual
(part number 9139B-901-01). These manuals are available for download at
LO patch panel and safety interlock
The S535 must have a single, direct connection between instrument lows and protective earth (safety
ground). The S500-LOPATCH-3KV panel provides this common LO connection and protective earth
(safety ground) reference.
Figure 45: S500-LOPATCH-3KV
The LO patch panel provides:
A common reference point for all the instrument low-side connections
In 4-wire systems, a common connection for the sense low terminals of the source-measure units
(SMUs)
Connections from low to sense low using a 100 kΩ resistor to enable autosensing
Prober safety
Hazardous voltages may be present on the probe card adapter, even after you disengage the
interlock. Cables can retain charges after the interlock is disengaged, exposing you to live
voltages that, if contacted, may cause personal injury or death.
Never attempt to touch or change a probe card when tests are running. You must be
absolutely certain that all tests have stopped before making contact with anything in the
vicinity of the probe card adapter. Also, never run tests without a probe card installed.
