Keithley 2520, Руководство пользователя, Страница: 320 / 329

I-4 Continuous Pulse Mode Model 2520 User’s Manual
Remote configuration over GPIB/IEEE-488
Related modes
There are three choices in the 2520 Trigger Count menu:
1.
Trigger count = Finite
— This mode will output up to 5000 pulses with a fixed
source current. Measurements are taken at each pulse, which means that the
minimum pulse delay time is about 2 milliseconds ± 400µs. In addition, the
minimum pulse delay is constrained by the maximum duty cycle of 4% above 1A
source levels. This means that requesting a duty cycle > 4% will cause the pulse
delay to be increased to give a duty cycle = 4%. For I < 1A, the maximum duty
cycle is about 15%.
2.
Trigger count = Inf
— This mode will output an infinite stream of fixed current
pulses. It is different from the Continuous Pulse mode because it offers measure-
ments (VLD, Detector 1 current, Detector 2 current). The measurement process
takes additional time, meaning that the minimum pulse delay time is about 2ms.
3.
Trigger count = Continuous Pulse
— This mode is explained above. It is similar
to count = Inf, but there are no measurements in this mode and the set pulse width
equals the actual pulse width.
Command Comment
*RST
:SOUR1:CURR:MODE FIX
:SOUR1:CURR 0.2
:SOUR1:PULS:DEL 0.00033
:SOUR1:PULS:WIDT 0.000001
:TRIG:COUN CONTINUOUS
:OUTP ON
:SYST:KEY 20
:SDC
:OUTP OFF Reset 2520
Set source mode to FIXed (not sweep)
Set current pulse amplitude to 200mA
Set pulse delay (time between pulses) to 330µs
Sets the pulse width to 1µs
Enables continuous pulsing mode
Turns Output ON
Begins continuous pulsing
Stops continuous pulsing*
Turns Output OFF
* SDC — Selected Device Clear. SDC is a GPIB Bus Command (see Table 10-1 ). Implementing this
command depends on the GPIB controller/driver. Refer to GPIB controlled documentation for specific
syntax.
Example: For Keithley GPIB: transmit (“UNL LISTEN <addr> SDC”, status)
For NI GPIB: Dev Clear (<Boardnum>, <addr>)
Where: <addr> is the GPIB address of the 2520 and <Boardnum> is the GPIB controller board
number, usually 0.