Limit Test Modes - Keithley 6430 Instruction Manual

11-4 Limit Testing

Limit test modes

There are two modes of operation for limit tests; grading and sorting. For Limit 1 test (com-
pliance), operation is similar for both limit test modes. If Limit 1 test fails, the "FAIL" message
is displayed and the testing process for that DUT (or DUT element) is terminated. A pass con-
dition allows the testing process to proceed to the next enabled limit test.
With the grading mode selected, each enable software test (Limit 2, 3, 5-12) is performed
until a failure occurs. When a test fails, the "FAIL" message is displayed and the testing pro-
cess for that DUT (or DUT element) is terminated.
With the sorting mode selected, each enabled software test (Limit 2, 3, 5-12) is performed
until a test passes. When a test passes, the "PASS" message is displayed and the testing process
for that DUT is terminated.
Binning
Even though no additional equipment is required to perform limit tests on the DUT, the
SourceMeter is typically used with a component handler to perform binning operations. After
the testing process, the DUT will be placed in an assigned bin.
For the grading mode, the binning system can be further automated by adding a scanner.
With the use of a scanner, the tests can be repeated (cycled) to test individual elements of a sin-
gle package (i.e., resistor network). See Binning systems for more information on using compo-
nent handlers and scanners to perform binning operations.
Operation overview
Grading mode
Grading mode limits operation is detailed by the flowchart in Figure 11-2. A test is only per-
formed if it is enabled. If disabled, operation proceeds to the next test. The following assumes
the first three limit tests are enabled and the digital output of the SourceMeter is connected to a
component handler for DUT binning. See Binning systems. If a handler is not used, ignore dig-
ital input/output (handler interface) actions.
With the limit tests properly configured, turn the SourceMeter output on and press the
LIMIT key. The testing process will start when the component handler sends the SOT (start-of-
test) strobe pulse to the SourceMeter. Note that if a handler is not used, testing will start when
LIMIT is pressed. Pressing LIMIT a second time terminates the testing process.
As shown in the flowchart, limit tests are performed after a measurement conversion.