DA1855A Differential Amplifier
3-12
ISSUED: July 2002
DA1855A-OM-E Rev A
Note
The effective voltage is always increased by the attenuator. It
therefore follows that any probe will increase the effective voltage
of both
V
COMP
and
V
DIFF
by its attenuation factor. For example, a
probe with a 100X attenuation factor will increase the effective full
scale range by 100.
Table 3-4. Effective Offset Range with
÷÷
100 Probe
Although the full scale range may be 10 kV or 15.5 kV, most
probes have a much lower maximum input voltage rating which
must not be exceeded.
Amplifier Output
The
AMPLIFIER OUTPUT
BNC is intended to be used with an
oscilloscope, spectrum analyzer or instrument having a 50
Ω
input resistance. The amplifier’s output impedance is 50
Ω
.
Without the 50
Ω
load, the amplifier gain will be uncalibrated and
will be approximately twice the amount indicated on the front
panel. Proper operation of the 1 MHz or 20 MHz bandwidth limit
filters requires an output load impedance of 50
Ω.
Remote Operation
A
REMOTE
connector on the rear panel of the DA1855A allows
total control of the instrument through a LeCroy oscilloscope
when connected to ProBus using the supplied cable. All of the
instrument functions can be controlled through the oscilloscope
user interface.
Remote control is also possible using commands sent through
the IEEE-488 bus or through RS-232 connected to the
Front Panel
Settings
Effective Offset Range
with
÷÷
100 Probe
Gain
Attenuation
V
COMP
V
DIFF
X1
÷÷
1
± 1.55 kV
± 1 kV
X1
÷÷
10
± 15.5 kV
± 10 kV
X10
÷÷
1
± 1.55 kV
± 100 V
x10
÷÷
10
± 15.5 kV
± 1 kV
