Avtech AVO-6HF-B, Инструкция по эксплуатации

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For chip-level testing, the output module is not used. In this case, a user-supplied
resistance of 50 Ohms should be connected in series with the chip, near the chip, and
the voltage waveform from the mainframe should be connected to the resistor/diode
series combination using coaxial cabling and/or coaxial probes. Care must be taken to
ensure that the resistor do not overheat. The resistance must be capable of dissipating
up to 50 Watts of average power, if the AVO-6HF-B is to be used over its full range of
capabilities.
-SMA OPTION
On units with the -SMA option, the standard OUT and GND solder terminals are
replaced with a single SMA female connector (with the OUT signal on the center
conductor, and the connector shield being GND). This is only suitable for connecting to
very short lengths of cable (less than 12 inches or 30 cm), since it is located after the
impedance-matching resistance. Any length of cabling will introduce transmission line
reflections due to the impedance mismatch. The cable will act as an inductance. The
load should be located as close as possible to the output connector (regardless of
whether solder terminals or the SMA connector is used).
If the user wishes to solder something close to this connector, the Amphenol 132140
male-SMA-to-solder-cup adapter could be used.
LENZ’S LAW AND INDUCTIVE VOLTAGE SPIKES
This instrument is designed to pulse resistive and diode loads and will exhibit a large
output spike when used to drive a load with significant inductance (as predicted by
LENZ'S LAW). For this reason the load should be connected to the output using low
inductance leads (as short as possible).
The voltage developed across an inductance L (in Henries), when the current is
changing at a rate given by dI
LOAD
/ dt (in Amps/sec), is: V
SPIKE
= L dI
LOAD
/ dt.
BASIC TEST ARRANGEMENT - WITHOUT OUTPUT MODULE
The AVO-6HF-B can be tested initially without the supplied output module. If the output
module is not used, the mainframe output generates up to 250 Volts, into a 50 Ohm
load, as illustrated below:
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