Specifications

Borrowing from the earlier
battery discharging example,
an external trigger or level
trigger (34411A only) can
begin the process of making
any measurement or
waveform capture.
Simultaneous measurements
with multiple DMMs
In automotive and aerospace
applications with mechanical-
electrical components, it is
common to make simultaneous
measurements of multiple
sensors. When you are using
switches, scanning high-voltage
signals at high speeds is
difficult without attenuation,
especially when you are using
FET switches. It is also diffi-
cult to scan signals that have
drastically different voltage
levels or different measurement
functions at high speeds. In
these situations, you can
connect multiple DMMs directly
to sensors with all external
trigger inputs in parallel to
a single trigger event.
The 34410A and 34411A use
hardware coupling to connect
external trigger inputs to the
measurement engine. Trigger
latency or jitter is less than
1 µs, so multiple 34411A DMMs
running at 50 k samples/s can
begin sampling at virtually the
same time. With each 34411A’s
reading storage at 1 million
readings, up to 20 seconds of
data can be captured in parallel.
Using four 34411A DMMs gives
an effective sample rate of
200 k samples/s, and readings
can be retrieved either
continuously at the 50 k rate
or in bursts of up to 270 k
readings/ second from each
34411A's reading storage.
For this particular application,
the four DMMs may be borrowed
from colleagues. It is easy to
set up a number of instruments
with complimentary triggering,
and the 100 Mbit LAN or USB
2.0 interfaces can easily keep up
with the combined data rates.
11
External or Level Trigger
Trigger Delay = 2 seconds
External Trigger
Effectively
200 k
Samples/s
34411A
DUT
Figure 6. Using an external trigger and a delay to synchronize sampling
Figure 7. Making simultaneous measurements on a DUT using
multiple multimeters