Agilent Technologies L4400 - Manual (Page 154)

142 L4400 User’s Guide
7 L4445A Microwave Switch/Attenuator Driver
Power Supplies
The switches and attenuators on the master remote module can be
powered from the L4445A or use an external power supply. All additional
slave modules must use an external power supply.
Each remote module has a terminal strip used to connect external switch
power. The three most common power supply voltages used by the
microwave switches and attenuators are:
• 5 Volts
• 15 Volts
• 24 Volts (most common)
+V
GND
EXTERNAL
POWER INPUT
30 VCD M
AX
+V
Power Consumption
Each 34945EXT can drive up to 2A continuously using an external power
supply. The actual amount of power available for the switches on each
34945EXT module varies with the type of switches used.
• Some switch types consume power even in their quiescent state.

Be sure to review the switch data sheets for the switches you are using.
• Set the pulse width to the minimum necessary to activate the switch
using the ROUTe:CHANnel:DRIVe:PULSe:WIDTh command.
• Add power supply recovery time using the
ROUTe:CHANnel:DRIVe:TIMe:RECovery command
• Use an external power supply if possible.
• When the source for the master remote module is set to internal, the
switching current or switching and quiescent currents drawn from the
internal power supply must not exceed the supply’s specification of: