Agilent Technologies 93000 SOC Series, Training Manual

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Device Characterization - DC Tests 14-3 Checking for Continuity and Short Circuits
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Agilent 93000 SOC Series User Training Part 1, October 2004
4
Enter a value for the current to be used for the test.
The current should be large enough to be measurable (at least 100 to
130 µA), but not so large as to damage the diode paths being
checked.
The value can be positive or negative. The polarity defines the
current direction. Positive current flows into the DUT pin.
5 Enter a value for the pass voltage minimum parameter.
6
Enter a value for the pass voltage maximum parameter.
7 Select whether you want to measure only with the polarity entered
in the test current, or to repeat the test with the opposite polarity, if
the first attempt passes.
Execute 8 Click the exec button.
For all pins in the pin list the AC relays are then closed to allow a func-
tional test to be executed.
Functional test cycles In order to test one pin the test function executes a functional test
consisting of four cycles:
• At all pins except the measured pin, during the four cycles of the
test the driver is set to 0 V and the tristate to off. This causes a
constant 0 V to be applied to the DUT. On the receive side a compare
to mask is executed (no measurement).
• At the pin to be measured the following sequence occurs:
In the first three cycles the driver is set to 0 V and tristate to on,
while the programmable load forces the test current. On the receive
side a compare to mask is executed. This allows the input voltage to
settle in case there are any external capacities.
In the fourth cycle the driver remains as for the previous 3 cycles.
The comparator measures the voltage. The high and low levels of the
comparator are set to pass volt. min and pass volt. max respec-
tively. A compare to intermediate state is executed, therefore a pass
is returned if the measured voltage lies between these two levels.