Operation
DA1855A-OM-E Rev A
ISSUED: July 2002
3-1
3
Operation
GENERAL INFORMATION
The DA1855A has been designed to be used with oscilloscopes
equipped with a ProBus interface. Connecting the Differential
Amplifier to the oscilloscope through the ProBus interface will
automatically control all the required settings from the
oscilloscope and will lock-out the DA1855A front panel controls.
All front panel controls are now accessible through the
oscilloscope user interface. The DA1855A user interface can be
viewed by pressing the
Coupling
button when the channel
connected to the DA1855A is selected. The DA1855A front panel
controls will operate manually when the Differential Amplifier is
connected to an oscilloscope not provided with a ProBus
interface.
Note:
Removing the ProBus interface cable with the differential
amplifier still powered up, requires the DA1855A to be
turned OFF and ON to access the front panel controls.
DYNAMIC RANGE
The basic amplifier dynamic range in X1 Gain and
÷
1
Attenuation
is ± 0.500 V. Changing the gain and or attenuation will affect both
the Differential Mode and Common Mode ranges.
The Differential Mode range is scaled by both gain and attenua-
tion, while the Common Mode range is scaled by attenuation
only. Refer to table 3-1.
Table 3-1. Dynamic Range
* Attenuation, Common Mode and Differential Mode ranges are
scaled with external probe attenuation. A
÷
10 probe will increase
all these values by a factor of 10.
Gain
Atten*
Differential Mode*
Common Mode*
1
÷
1
± 0.5 V
± 15.5 V
1
÷
10
± 5.0 V
± 155 V
10
÷
1
± 50 mV
± 15.5 V
10
÷
10
± 0.5 V
± 155 V
