Agilent Technologies L4400 - Manual (Page 160)

148 L4400 User’s Guide
7 L4445A Microwave Switch/Attenuator Driver
Using Pulse Drive
To use the pulse drive mode, send the
ROUTe:CHANnel:DRIVe:PULSe:MODE ON command or pair two channels
with the ROUTe:CHANnel:DRIVe:PAIRed:MODE command. The diagram
below illustrates the pulse drive for two channels (switches) and the
relationship of the drive parameters to the power supply requirements.
T(Setttle)
T(Recovery)
Drive Ch 1
Drive Ch2
Start Drive
Channel 1 Start Drive
Channel 2 Channel 1 Position
Indicators Evaluated
T(Pulse)
As shown in the diagram, the drive is applied to channel 1 and held for
the T(Pulse) time set using the
ROUTe:CHANnel:DRIVe:PULSe:WIDTh
command. Drive is applied to channel 2 only after a power supply
recovery period has elapsed T(Recovery). The power supply recovery time
is set using the
ROUTe:CHANnel:DRIVe:TIMe:RECovery command. This
parameter may be set individually for each channel or will default to 0.0
ms following either a
SYSTem:RMODule:RESet or
ROUTe:RMODule:BANK:PRESet command.
If you are verifying the channel operation (see page 149 ), you may also
specify a T(Settle) parameter. During T(Settle) the switch is considered
‘busy’. This parameter ensures the switch has had time to change state
before the verification. This parameter may be set individually for each
channel or will default to 0.0 ms following either a
SYSTem:RMODule:RESet
or ROUTe:RMODule:BANK:PRESet command.
Unlike other switch modules, the L4445A will always pulse a channel in
response to a
ROUTe:OPEN or ROUTe:CLOSe command. For example, sending
ROUTe:CLOSe to a channel three times in a row will result in three output
pulses.
N O T E
A single drive channel operating in pulse mode with channel
verification (see
page 149 ) turned off (default) will report the channel as
‘stateless’ and the ROUTe:CLOSe? query will return an error. Single
drive pulsed channels must have verification enabled
(
ROUTe:CHANnel:VERify ON ) to query the channel state using the
ROUTe:CLOSe? query.