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 with:

Source

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

PyPI

pip install ConstellationDAQ[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	5s
CURRENT	Current output	Float	LAST_VALUE	5s
IN_COMLIANCE	If in compliance	Bool	LAST_VALUE	5s

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

Framework Parameters

This satellite inherits the following framework parameters from its base classes:

Parameters inherited from Satellite