Agilent Technologies L4400 - Manual (Page 197)

L4445A Microwave Switch/Attenuator Driver 7
L4400 User’s Guide 185
Paired Drive With Separate Position Indicators
The simplified schematic below illustrates the connection for a dual drive
switch with separate position indicators. The position indicators for this
type of switch are independent relay contacts that are mechanically linked
to the RF switch position.
The RF paths are not shown in the simplified diagram. The coils are
driven in open collector mode. The position indicator is set so that a high
level indicates an active switch. The logic level of the position indicator
can be inverted using the
ROUTe:CHANnel:VERify:POLarity command.
As shown, Channel 01 was pulsed to close Coil A. The corresponding
position indicator also closed. Closing position indicator A opens position
indicator B.
The schematic shown is similar to the Agilent N181x series of switches.
34945EXT Y1155A
Distribution
Board Switch
IND 11
IND 1
+VI
+VR
DRV 1
DRV 11
Open Collector
Output Drivers
Logic Gate
Sense
Pull Down
Resistor
A B
Coil A Coil B