Keithley Satellite#

Satellite controlling a Keithley power supply

Description#

This satellite uses the RS-232 serial port of Keithley Source Measure Units to control them remotely. The satellite can control a single Keithley SMU and operate it as voltage source. Among other settings, it is possible to configure the over-voltage protection (OVP), the current compliance as well as the target voltage. Voltage changes are performed as ramps, i.e. the voltage is incremented or decremented in small steps.

Note

This satellite requires write access to the serial port or USB-to-serial converter the device is attached to. It is recommended to not run this satellite with root privileges but to allow the regular user access to the required port instead. On Unix, if the port is e.g. /dev/ttyUSB0, the group can be found via stat /dev/ttyUSB0 (the Gid entry). If the group is e.g. dialout, the permissions can be given with sudo usermod -a -G dialout $USER. A restart is required for the changes to be effective.

Requirements#

The Keithley satellite requires the [keithley] component, which can be installed e.g. via:

pip install --no-build-isolation -e .[keithley]

Supported devices#

The device model to be controlled by this satellite can be selected via the device configuration parameter. The following devices are current supported:

`2410`#

The 2410 device supports the Keithley Series 2400 SourceMeter in RS-232 mode. The following serial communication settings are required and have to be configured on the SMU before starting the satellite. They can be found at MENU -> COMMUNICATION -> RS-223

BAUD: 19200
BITS: 8
PARITY: EVEN
TERMINATOR: <CR+LF>
FLOW-CTRL: NONE

Possible terminals are front and rear.

Parameters#

Parameter	Description	Type	Default Value
`device`	Device	String	-
`port`	Serial port to connect to	String	-
`terminal`	Terminal output to control	String	-
`voltage`	Target output voltage	Float	-
`voltage_step`	Voltage step in which to ramp to target voltage	Float	-
`settle_time`	Time to wait before continuing with the next voltage step	Float	-
`ovp`	Voltage limit for over-voltage protection	Float	-
`compliance`	Current limit in Ampere	Float	-

Metrics#

Metric	Description	Value Type	Metric Type	Interval
`VOLTAGE`	Voltage output	Float	`LAST_VALUE`	10s
`CURRENT`	Current output	Float	`LAST_VALUE`	10s
`IN_COMLIANCE`	If in compliance	Bool	`LAST_VALUE`	10s

Custom Commands#

Command	Description	Arguments	Return Value	Allowed States
`in_compliance`	Check if the current is in compliance	-	Bool	`ORBIT`, `RUN`
`read_output`	Reads voltage, current and timestamp	-	Dictionary	`ORBIT`, `RUN`