Features
 The MultiTrace is much more than just an automated curve
tracer. It is an advanced electrical characterization system that can also do Latch-Up
testing, IDDQ testing, and DC Parametric measurements. And with the MultiTrace's flexible
software, almost any type of DC electrical measurement can be made.
AUTOMATED Curve
Tracing
Curve tracing of all the pins on a device is automated. Once the test is
setup using a one-page test-setup menu, testing is a simple matter of pressing a button.
Each pin is then curve traced quickly and automatically. The results can be shown as
an"All Pins" view (where all the pins are shown at the same time, overlapped on
top of each other) or one pin at a time.
Comparison to
Known Good Device
 Once a Known Good Device is curve traced, its data can
be stored in the MultiTrace computer's hard disk and then used to compare to other test
devices. Each pin curve can be compared graphically, as in the curve trace to the left, or
the MultiTrace's Compare Trace function can
be used to automatically compare every pin of the test device to the Known Good Device. A
list of the failed and passed pins is then displayed.
Powered Curve Tracing
Curve tracing can also be done under powered conditions where the device is powered up
to its normal operating voltage (VDD is applied to device) and the inputs are biased. With
this type of test, leakage measurements can be more accurately acquired and DC parameters
can be measured.
DC Parametric Testing
Once properly powered, DC parameters such as output drive, output leakage, Vol, Voh,
tri-state leakage, and IOS be measured. Other parameters include transistor family of
curves, resistance, Vil, Vih, Switching Voltage, and breakdown voltage.
Plot IDD During Curve Trace
 During the powered curve tracing of a pin, the IDD of the device can
be plotted as a function of the voltage sweep of the pin. With this capability, the
correct biasing of a pin (whether a "high" bias or a "low" bias) can
be determined in order to put the device in the desired IDD state (some select pins can
control whether the device is in a high or low Supply Current state).
Supply Current Testing
The MultiTrace also has a dedicated test setup for Supply Current
measurements. Using the same device setup as in the powered curve trace, a single IDD
value, at a given VDD, or a plot of IDD vs. VDD can be measured.
IDDQ Testing
Used in conjunction with the MultiTrace's vectoring software, IDDQ
testing can also be done. The vector size is unlimited because of the unique way in which
the vector file is used in the MultiTrace. A range of options exist for IDDQ testing.
Latch-Up
Latch-Up is a possible failure condition inherent within CMOS technology
devices. With a large injection of current or with a very large increase in the VDD
voltage, devices designed without proper latch-up resistant considerations will show a
supply current that continues to rise after the trigger current has stopped, sometimes
destroying the device.
With the Latch-Up option, the MultiTrace is able to do Post-VDD pulse
(JEDEC standard), Pre-VDD pulse, and VDD OverVoltage latch-up tests. The custom Latch-Up
Report Generator that comes with the option automatically generates a full report for
every pin that was tested.
Vector Pre-Conditioning
Advanced techniques, such as pre-conditioning can also be done using the
MultiTrace System. Using the MultiTrace vectoring software, vectors can be applied to the
device to place the device in the desired state before curve tracing, IDD testing, or
Latch-Up testing. Many complex devices need to be put in a specific state before a test is
valid. Vector pre-conditioning is mostly used for the IDD and the Latch-Up tests.
Multiple VDD Voltages
Many of today's devices have more than one VDD voltage, with a mix of
3.3V and 5V VDD's being most common. Bi-CMOS devices also require more than one voltage
value to power up the device. In order to test these devices properly under powered
conditions, at least 5 SMU's (Source and Measurement Units), are required. With a 6-bus
configuration MultiTrace, such as the A2R4 configuration, up to 6 SMU's can be connected
to a given device, thus allowing three separate VDD voltage values.
Fixturing
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Fixturing is accomplished by the use of a universal PGA ZIF socket. Connection is
carried from the device, on the ZIF socket, to the SMU's through the switching matrix. Any
DIP or PGA type packaged device can be directly inserted into the PGA ZIF socket. Other
types of packages, such as PLCC's, QFP's, SOIC's, and BGA's, use a burn-in socket + PCB
adapter (which converts the burn-in socket footprint to a PGA footprint) combination to
connect directly to the PGA ZIF socket. This type of fixturing has the advantage that
connection is absolutely reliable and is relatively inexpensive. Remote fixtures
allow MultiTrace testing with a microscope for Liquid Crystal Hot Spot Analysis or with an
Emission Microscope. |
Self-Calibration and
Diagnostic Software
All MultiTrace systems come with self-calibration and self-diagnostic
software that checks for continuity within the system, switch board failures, and errors
with the measurement or setting values.
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