Keithley 2280 Series User manual

Precision Measurement DC Power Supplies
Reference Manual
077085501 / February 2015
*P077085501*
077085501
A Tektr onix Company
Series 2280
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - TestEquipmentDepot.com

Precision Measurement DC Power Supplies
Reference Manual
© 2015, Keithley Instruments
Cleveland, Ohio, U.S.A.
All rights reserved.
Any unauthorized reproduction, photocopy, or use of the information herein, in whole or in part,
without the prior written approval of Keithley Instruments is strictly prohibited.
All Keithley Instruments product names are trademarks or registered trademarks of Keithley
Instruments. Other brand names are trademarks or registered trademarks of their respective
holders.
Document number: 077085501 / February 2015
Series 2280

Safety precautions
The following safety precautions should be observed before using this product and any associated instrumentation. Although
some instruments and accessories would normally be used with nonhazardous voltages, there are situations where hazardous
conditions may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety precautions
required to avoid possible injury. Read and follow all installation, operation, and maintenance information carefully before using
the product. Refer to the user documentation for complete product specifications.
If the product is used in a manner not specified, the protection provided by the product warranty may be impaired.
The types of product users are:
Responsible body is the individual or group responsible for the use and maintenance of equipment, for ensuring that the
equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately trained.
Operators use the product for its intended function. They must be trained in electrical safety procedures and proper use of the
instrument. They must be protected from electric shock and contact with hazardous live circuits.
Maintenance personnel perform routine procedures on the product to keep it operating properly, for example, setting the line
voltage or replacing consumable materials. Maintenance procedures are described in the user documentation. The procedures
explicitly state if the operator may perform them. Otherwise, they should be performed only by service personnel.
Service personnel are trained to work on live circuits, perform safe installations, and repair products. Only properly trained
service personnel may perform installation and service procedures.
Keithley Instruments products are designed for use with electrical signals that are measurement, control, and data I/O
connections, with low transient overvoltages, and must not be directly connected to mains voltage or to voltage sources with high
transient overvoltages. Measurement Category II (as referenced in IEC 60664) connections require protection for high transient
overvoltages often associated with local AC mains connections. Certain Keithley measuring instruments may be connected to
mains. These instruments will be marked as category II or higher.
Unless explicitly allowed in the specifications, operating manual, and instrument labels, do not connect any instrument to mains.
Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable connector jacks or test
fixtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage levels greater than
30 V RMS, 42.4 V peak, or 60 VDC are present. A good safety practice is to expect that hazardous voltage is present in any
unknown circuit before measuring.
Operators of this product must be protected from electric shock at all times. The responsible body must ensure that operators
are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential
human contact. Product operators in these circumstances must be trained to protect themselves from the risk of electric shock . If
the circuit is capable of operating at or above 1000 V, no conductive part of the circuit may be exposed.
Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedance-limited
sources. NEVER connect switching cards directly to AC mains. When connecting sources to switching cards, install protective
devices to limit fault current and voltage to the card.
Before operating an instrument, ensure that the line cord is connected to a properly-grounded power receptacle. Inspect the
connecting cables, test leads, and jumpers for possible wear, cracks, or breaks before each use.
When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main input
power disconnect device must be provided in close proximity to the equipment and within easy reach of the operator.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under
test. ALWAYS remove power from the entire test system and discharge any capacitors before: connecting or disconnecting
cables or jumpers, installing or removing switching cards, or making internal changes, such as installing or removing jumpers.
Do not touch any object that could provide a current path to the common side of the circuit under test or power line (earth)
ground. Always make measurements with dry hands while standing on a dry, insulated surface capable of withstanding the
voltage being measured.
For safety, instruments and accessories must be used in accordance with the operating instructions. If the instruments or

accessories are used in a manner not specified in the operating instructions, the protection provided by the equipment may be
impaired.
Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications and operating
information, and as shown on the instrument or test fixture panels, or switching card.
When fuses are used in a product, replace with the same type and rating for continued protection against fire hazard.
Chassis connections must only be used as shield connections for measuring circuits, NOT as protective earth (safety ground)
connections.
If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation requires the use
of a lid interlock.
If a screw is present, connect it to protective earth (safety ground) using the wire recommended in the user documentation.
The symbol on an instrument means caution, risk of danger. The user must refer to the operating instructions located in the
user documentation in all cases where the symbol is marked on the instrument.
The symbol on an instrument means caution, risk of electric shock. Use standard safety precautions to avoid personal
contact with these voltages.
The symbol on an instrument shows that the surface may be hot. Avoid personal contact to prevent burns.
The symbol indicates a connection terminal to the equipment frame.
If this symbol is on a product, it indicates that mercury is present in the display lamp. Please note that the lamp must be
properly disposed of according to federal, state, and local laws.
The WARNING heading in the user documentation explains dangers that might result in personal injury or death. Always read
the associated information very carefully before performing the indicated procedure.
The CAUTION heading in the user documentation explains hazards that could damage the instrument. Such damage may
invalidate the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and all test cables.
To maintain protection from electric shock and fire, replacement components in mains circuits — including the power
transformer, test leads, and input jacks — must be purchased from Keithley Instruments. Standard fuses with applicable national
safety approvals may be used if the rating and type are the same. Other components that are not safety-related may be
purchased from other suppliers as long as they are equivalent to the original component (note that selected parts should be
purchased only through Keithley Instruments to maintain accuracy and functionality of the product). If you are unsure about the
applicability of a replacement component, call a Keithley Instruments office for information.
To clean an instrument, use a damp cloth or mild, water-based cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill on the instrument. Products that consist of a circuit b oard with
no case or chassis (e.g., a data acquisition board for installation into a computer) should never require cleaning if handled
according to instructions. If the board becomes contaminated and operation is affected, the board should be returned to the
factory for proper cleaning/servicing.
Safety precaution revision as of January 2013.

Introduction .......................................................................................................... 1-1
Welcome ......................................................................................................................... 1-1
Extended warranty........................................................................................................... 1-1
Contact information ......................................................................................................... 1-1
CD-ROM contents ........................................................................................................... 1-2
Organization of manual sections ...................................................................................... 1-2
Key features .................................................................................................................... 1-3
Standard accessories ...................................................................................................... 1-3
Optional accessories ....................................................................................................... 1-4
Available services ............................................................................................................ 1-5
General ratings ................................................................................................................ 1-5
General operation ................................................................................................. 2-1
Front-panel overview ....................................................................................................... 2-1
Rear-panel overview ........................................................................................................ 2-3
Front-panel user interface ................................................................................................ 2-4
Home screens ........................................................................................................................... 2-4
Menu overview ........................................................................................................................ 2-10
Adjusting the backlight brightness and timer ........................................................................... 2-21
Installing the system ...................................................................................................... 2-22
Handle and bumpers ............................................................................................................... 2-22
Dimensions ............................................................................................................................. 2-27
Power the instrument on and off ............................................................................................. 2-31
Test connections ........................................................................................................... 2-33
Front-panel connector ............................................................................................................. 2-34
Rear-panel output mating connector ....................................................................................... 2-35
Two-wire local sense connection ............................................................................................ 2-36
Four-wire sense connection .................................................................................................... 2-36
Open leads detection .............................................................................................................. 2-37
Reverse sense leads ............................................................................................................... 2-39
Remote communication interfaces ................................................................................. 2-40
Supported remote interfaces ................................................................................................... 2-40
GPIB communication .............................................................................................................. 2-40
LAN communication ................................................................................................................ 2-43
USB communications .............................................................................................................. 2-55
How to install the Keithley I/O Layer ....................................................................................... 2-61
Set voltage and current limit........................................................................................... 2-62
Constant voltage (CV) and constant current (CC) mode ......................................................... 2-63
Select a measurement function ...................................................................................... 2-65
Select a specific measurement range ............................................................................ 2-65
Selecting a specific measurement range ................................................................................ 2-66
Using Autoranging for Current Measurements ........................................................................ 2-66
Protection ...................................................................................................................... 2-67
Table of Contents

Table of Contents Series 2280 Precision Measurement DC Power Supplies Reference Manual
Overvoltage protection ............................................................................................................ 2-67
Overcurrent protection ............................................................................................................ 2-68
Overtemperature protection .................................................................................................... 2-69
Overprotection error ................................................................................................................ 2-70
Maximum voltage limits ........................................................................................................... 2-70
Saving setups ................................................................................................................ 2-71
Save a user setup ................................................................................................................... 2-72
Recall a user setup ................................................................................................................. 2-73
Specify a default setup ............................................................................................................ 2-73
Using the event log ........................................................................................................ 2-74
Information provided for each event log entry ......................................................................... 2-74
Save the event log to an external flash drive........................................................................... 2-74
Clear the event log .................................................................................................................. 2-74
System information ........................................................................................................ 2-75
Instrument sounds ......................................................................................................... 2-75
Resets ........................................................................................................................... 2-76
Reset the instrument ............................................................................................................... 2-76
Functions and features ......................................................................................... 3-1
Instrument access ........................................................................................................... 3-1
Changing the instrument access mode ..................................................................................... 3-1
Changing the password ............................................................................................................ 3-2
Graph .............................................................................................................................. 3-2
Changing the window position and zoom .................................................................................. 3-3
Adjusting the scale and offset of Y-Axis .................................................................................... 3-4
Output delay, slew rate, and source delay ........................................................................ 3-5
Output delay .............................................................................................................................. 3-5
Slew rate ................................................................................................................................... 3-6
Source delay ............................................................................................................................. 3-6
Reading buffer ................................................................................................................. 3-7
Effects of reset and power cycle on buffer ................................................................................ 3-7
Buffer fill status.......................................................................................................................... 3-7
Setting reading buffer size and buffer mode.............................................................................. 3-8
Viewing and saving buffer content ............................................................................................ 3-9
Configuring the statistics applied to data in the buffer ............................................................. 3-12
Clearing buffer......................................................................................................................... 3-15
Automatically clearing buffer ................................................................................................... 3-16
Digital I/O ...................................................................................................................... 3-16
Digital I/O port ......................................................................................................................... 3-16
Configuring digital I/O lines ..................................................................................................... 3-19
Trigger model ................................................................................................................ 3-21
Idle and initiate ........................................................................................................................ 3-23
Arm layer ................................................................................................................................. 3-23
Trigger layer ............................................................................................................................ 3-23
Source, source delay and measure actions ............................................................................ 3-23
Counter ................................................................................................................................... 3-24
Meter complete ....................................................................................................................... 3-24
Running the trigger model ....................................................................................................... 3-24
Level trigger .................................................................................................................. 3-26
Configuring a voltage level trigger ........................................................................................... 3-26
Configuring a current level trigger ........................................................................................... 3-28

Series 2280 Precision Measurement DC Power Supplies Reference Manual Table of Contents
List operation ................................................................................................................. 3-30
Configuring a list ..................................................................................................................... 3-31
Importing a list from an external USB flash drive .................................................................... 3-33
Exporting a list to an external USB flash drive ........................................................................ 3-34
Running a list .......................................................................................................................... 3-34
Aborting a list .......................................................................................................................... 3-43
Sink operation ............................................................................................................... 3-44
Reset default values ...................................................................................................... 3-44
Default value ........................................................................................................................... 3-45
Measurement optimization ................................................................................... 4-1
Introduction ..................................................................................................................... 4-1
Optimizing either measurement accuracy or speed .......................................................... 4-1
Resolution ................................................................................................................................. 4-2
NPLC ........................................................................................................................................ 4-3
Autozero measurements ........................................................................................................... 4-4
Displayed digits ......................................................................................................................... 4-5
Filtering measurement data....................................................................................................... 4-6
Math calculations that you can apply to measurements .................................................. 4-10
mx+b ....................................................................................................................................... 4-10
Setting mx+b math operations ................................................................................................ 4-10
Relative offset................................................................................................................ 4-11
Establishing a relative offset value .......................................................................................... 4-12
Displayed measurements .............................................................................................. 4-13
Select the source of readings .................................................................................................. 4-14
Application examples ........................................................................................... 5-1
Simple voltage output and current measurement ............................................................. 5-1
Equipment required ................................................................................................................... 5-1
Set up remote communications ................................................................................................. 5-1
Device connections ................................................................................................................... 5-2
Set the voltage and current limit ................................................................................................ 5-2
Configure and execute a 10-step linear list sweep............................................................ 5-3
Equipment required ................................................................................................................... 5-3
Set up remote communications ................................................................................................. 5-4
Device connections ................................................................................................................... 5-4
Configure a 10-step linear list sweep ........................................................................................ 5-4
Execute a 10-step linear list sweep ........................................................................................... 5-5
Perform a fast current load measurement ........................................................................ 5-6
Equipment required ................................................................................................................... 5-7
Set up remote communications ................................................................................................. 5-7
Device connections ................................................................................................................... 5-8
Measure the fast current load changes ..................................................................................... 5-9
Introduction to SCPI commands........................................................................... 6-1
Introduction to SCPI ........................................................................................................ 6-1
Command messages ................................................................................................................ 6-1
Command execution rules......................................................................................................... 6-2
SCPI command programming notes ................................................................................ 6-2

Table of Contents Series 2280 Precision Measurement DC Power Supplies Reference Manual
SCPI command formatting ........................................................................................................ 6-2
Using the SCPI command reference ......................................................................................... 6-4
SCPI command reference ..................................................................................... 7-1
Common commands........................................................................................................ 7-1
*CLS .......................................................................................................................................... 7-2
*ESE ......................................................................................................................................... 7-2
*ESR? ....................................................................................................................................... 7-3
*IDN? ........................................................................................................................................ 7-4
*OPC ......................................................................................................................................... 7-4
*LANG? ..................................................................................................................................... 7-5
*RCL ......................................................................................................................................... 7-5
*RST ......................................................................................................................................... 7-6
*SAV ......................................................................................................................................... 7-6
*SRE ......................................................................................................................................... 7-7
*STB? ........................................................................................................................................ 7-8
*TRG ......................................................................................................................................... 7-9
*TST? ........................................................................................................................................ 7-9
*WAI ........................................................................................................................................ 7-10
:ABORt[n] ................................................................................................................................ 7-11
:CONFigure[n]:<function> ....................................................................................................... 7-11
:FETCh[n]? .............................................................................................................................. 7-12
:FORMat:ELEMents ................................................................................................................ 7-13
:FORCe:TRIGger .................................................................................................................... 7-15
:MEASure[n]:<function>? ........................................................................................................ 7-16
:READ[n]? ............................................................................................................................... 7-17
ARM subsystem ............................................................................................................ 7-17
:ARM[:SEQuence[n]]:COUNt .................................................................................................. 7-18
:ARM[:SEQuence[n]]:SOURce ................................................................................................ 7-18
CALCulate subsystem ................................................................................................... 7-19
:CALCulate[1]:<function>:FORMat.......................................................................................... 7-19
:CALCulate[1]:<function>:KMATh:MBFactor ........................................................................... 7-20
:CALCulate[1]:<function>:KMATh:MMFactor .......................................................................... 7-21
:CALCulate[1]:<function>:KMATh:MUNits............................................................................... 7-22
:CALCulate[1]:<function>:STATe ............................................................................................ 7-23
:CALCulate2:DATA? ............................................................................................................... 7-24
:CALCulate2:FORMat ............................................................................................................. 7-25
:CALCulate2:FORMat:ELEMents ............................................................................................ 7-27
:CALCulate2:FUNCtion ........................................................................................................... 7-28
:CALCulate2:IMMediate .......................................................................................................... 7-29
:CALCulate2:STATe ................................................................................................................ 7-31
CALibration subsystem .................................................................................................. 7-31
:CALibration:PROTected:CANCel ........................................................................................... 7-32
:CALibration:PROTected:CODE ............................................................................................. 7-32
:CALibration:PROTected:COUNt? .......................................................................................... 7-33
:CALibration:PROTected:DATA? ............................................................................................ 7-33
:CALibration:PROTected:DATE .............................................................................................. 7-34
:CALibration:PROTected[:DC[n]]:STEP<step> ....................................................................... 7-35
:CALibration:PROTected[:DC[n]]:STEP<step>:DATA ............................................................. 7-37
:CALibration:PROTected:SAVE .............................................................................................. 7-39
:CALibration:PROTected:STATe............................................................................................. 7-40
Digital subsystem .......................................................................................................... 7-40
:DIGital:LINE<n>:FUNCtion .................................................................................................... 7-41
:DIGital:LINE<n>:MANual:INPut:DATA? ................................................................................. 7-41
DISPlay subsystem ....................................................................................................... 7-42
:DISPlay:BRIGhtness .............................................................................................................. 7-42

Series 2280 Precision Measurement DC Power Supplies Reference Manual Table of Contents
:DISPlay:CLEar ....................................................................................................................... 7-43
:DISPlay:SCREen ................................................................................................................... 7-43
:DISPlay:USER:TEXT[:DATA]................................................................................................. 7-44
INITiate subsystem ........................................................................................................ 7-44
:INITiate[n]:CONTinuous ......................................................................................................... 7-45
:INITiate[n][:IMMediate] ........................................................................................................... 7-45
MMEMory subsystem .................................................................................................... 7-46
:MMEMory:LOAD:SETup ........................................................................................................ 7-46
:MMEMory:SAVE:SETup ........................................................................................................ 7-46
OUTPut subsystem ....................................................................................................... 7-47
:OUTPut:DELay:FALLing ........................................................................................................ 7-47
:OUTPut:DELay:RISing ........................................................................................................... 7-48
:OUTPut:DELay:STATe .......................................................................................................... 7-49
:OUTPut:PROTection:CLEar................................................................................................... 7-49
:OUTPut:PROTection:TRIPped?............................................................................................. 7-50
:OUTPut[:STATe] .................................................................................................................... 7-51
SENSe subsystem......................................................................................................... 7-51
:SENSe[n]:FUNCtion ............................................................................................................... 7-51
:SENSe[n]:<function>:AVERage:COUNt ................................................................................ 7-52
:SENSe[n]:<function>:AVERage[:STATe] ............................................................................... 7-53
:SENSe[n]:<function>:AVERage:TCONtrol ............................................................................. 7-54
:SENSe[n]:<function>:AVERage:WINDow .............................................................................. 7-55
:SENSe[n]:<function>:DIGits ................................................................................................... 7-56
:SENSe[n]:<function>:NPLCycles ........................................................................................... 7-57
:SENSe[n]:<function>:RANGe ................................................................................................ 7-58
:SENSe[n]:<function>:RANGe:AUTO ..................................................................................... 7-59
:SENSe[n]:<function>:REFerence........................................................................................... 7-60
:SENSe[n]:<function>:REFerence:ACQuire ............................................................................ 7-61
:SENSe[n]:<function>:REFerence:STATe............................................................................... 7-62
:SENSe[n]:<function>:RESolution ........................................................................................... 7-63
SOURce subsystem ...................................................................................................... 7-63
[:SOURce[n]]:DELay ............................................................................................................... 7-64
[:SOURce[n]]:DELay:STATe ................................................................................................... 7-64
[:SOURce[n]]:<function>:PROTection[:LEVel] ........................................................................ 7-65
[:SOURce[n]]:<function>[:LEVel][:IMMediate][:AMPLitude] ..................................................... 7-66
[:SOURce[n]]:VOLTage:LIMit[:AMPLitude].............................................................................. 7-67
[:SOURce[n]]:VOLTage:SLEW:RISing .................................................................................... 7-67
[:SOURce[n]]:VOLTage:SLEW:FALLing ................................................................................. 7-68
[:SOURce[n]]:LIST<list number>:<element> ........................................................................... 7-69
[:SOURce[n]]:LIST<list number>:<element>:APPEnd ............................................................ 7-70
[:SOURce[n]]:LIST<list number>:<element>:POINts? ............................................................ 7-71
[:SOURce[n]]:LIST:END:ZERO ............................................................................................... 7-71
[:SOURce[n]]:LIST:HTIMe ....................................................................................................... 7-72
[:SOURce[n]]:LIST:LOAD:USB ............................................................................................... 7-72
[:SOURce[n]]:LIST:MCOMPlete .............................................................................................. 7-73
[:SOURce[n]]:LIST:RCL .......................................................................................................... 7-74
[:SOURce[n]]:LIST:SAVE:INTErnal ......................................................................................... 7-78
[:SOURce[n]]:LIST:SAVE:USB................................................................................................ 7-78
[:SOURce[n]]:LIST:STATe ...................................................................................................... 7-79
STATus subsystem ....................................................................................................... 7-82
:STATus:MEASurement[:EVENt]? .......................................................................................... 7-83
:STATus:MEASurement:ENABle ............................................................................................ 7-83
:STATus:MEASurement:INSTrument[:EVENt]? ...................................................................... 7-84
:STATus:MEASurement:INSTrument:ENABle ........................................................................ 7-84
:STATus:MEASurement:INSTrument:ISUMmary[:EVENt]? .................................................... 7-85
:STATus:MEASurement:INSTrument:ISUMmary:ENABle ...................................................... 7-85
:STATus:MEASurement:INSTrument:ISUMmary:CONDition? ................................................ 7-86