Keithley 7752 User manual

www.keithley.com
A GREATER MEASURE OF CONFIDENCE
Model 7751/7752/7753 Switching Modules
User’s Guide
PA-823 Rev. B / Sept 2003
The Models 7751/7752/7753 can be
used with Keithley’s Model 2790.

Safety Precautions
The following safety precautions should be observed before using
this product and any associated instrumentation. Although some in-
struments and accessories would normally be used with non-haz-
ardous voltages, there are situations where hazardous conditions
may be present.
This product is intended for use by qualified personnel who recog-
nize shock hazards and are familiar with the safety precautions re-
quired to avoid possible injury. Read and follow all installation,
operation, and maintenance information carefully before using the
product. Refer to the manual for complete product specifications.
If the product is used in a manner not specified, the protection pro-
vided by the product 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 en-
suring 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 instru-
ment. 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 de-
scribed in the manual. 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, and perform
safe installations and repairs of products. Only properly trained ser-
vice personnel may perform installation and service procedures.
Keithley products are designed for use with electrical signals that
are rated Installation Category I and Installation Category II, as de-
scribed in the International Electrotechnical Commission (IEC)
Standard IEC 60664. Most measurement, control, and data I/O sig-
nals are Installation Category I and must not be directly connected
to mains voltage or to voltage sources with high transient over-volt-
ages. Installation Category II connections require protection for
high transient over-voltages often associated with local AC mains
connections. Assume all measurement, control, and data I/O con-
nections are for connection to Category I sources unless otherwise
marked or described in the Manual.
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 30V RMS, 42.4V
peak, or 60VDC 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 pre-
vented access and/or insulated from every connection point. In
some cases, connections must be exposed to potential human con-
tact. 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 volts, 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 con-
necting sources to switching cards, install protective devices to lim-
it fault current and voltage to the card.
Before operating an instrument, make sure the line cord is connect-
ed 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 dis-
connect device must be provided, in close proximity to the equip-
ment 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 jump-
ers, 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 com-
mon 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.
The instrument and accessories must be used in accordance with its
specifications and operating instructions or the safety of the equip-
ment may be impaired.
Do not exceed the maximum signal levels of the instruments and ac-
cessories, as defined in the specifications and operating informa-
tion, and as shown on the instrument or test fixture panels, or
switching card.
When fuses are used in a product, replace with same type and rating
for continued protection against fire hazard.
Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.
If you are using a test fixture, keep the lid closed while power is ap-
plied to the device under test. Safe operation requires the use of a
lid interlock.
5/02

If or is present, connect it to safety earth ground using the
wire recommended in the user documentation.
The symbol on an instrument indicates that the user should re-
fer to the operating instructions located in the manual.
The symbol on an instrument shows that it can source or mea-
sure 1000 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.
The WARNING heading in a manual explains dangers that might
result in personal injury or death. Always read the associated infor-
mation very carefully before performing the indicated procedure.
The CAUTION heading in a manual 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 Instru-
ments. 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 se-
lected 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 board with no
case or chassis (e.g., data acquisition board for installation into a
computer) should never require cleaning if handled according to in-
structions. If the board becomes contaminated and operation is af-
fected, the board should be returned to the factory for proper
cleaning/servicing.
!

PA-823 Rev. B / 9-03
Models 7751/7752/7753 Switching Modules
User’s Guide
Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139
[phone]
www.keithley.com
Introduction
The Models 7751, 7752, and 7753 are used with the Model 2790 SourceMeter Switch System. Safety fea-
tures are integrated into the design of the modules to help safeguard the user and the module. With proper
use of the module and the Model 2790 mainframe, risk of ignition is minimal.
The 7751, 7752, and 7753 modules have a built-in programmable constant I-source to perform low resis-
tance measurements. The 7751 and 7753 modules also have a built-in programmable V-source and an I/V
converter. These features allow the 7751 and 7753 modules to be used with the Digital Multimeter (DMM)
of the Model 2790 to measure high resistance.
NOTE Details on using the 7751, 7752, and 7753 modules are provided in Sections 1, 2, and 5
of the Model 2790 User’s Manual.
WARNING It is the responsibility of the user to ensure that external protection is provided, either
by an inherently safe electrical barrier and/or a safety barrier around the DUT or air-
bag, to prevent injury in case of detonation. The user must take additional precautions
when working with hazardous voltages. A shock hazard exists when >42V is present in
the system.
WARNING DO NOT apply external sources to the 7751, 7752, or 7753 module. Only the sources
provided in the modules should be used for the test system.
Switching matrix
The switching matrix provides four banks of input for the DUT. Each bank provides inputs for 4-wire con-
nections. Each bank also has a built-in short available for HIPOT testing. The switching scheme of the
matrix provides the versatility needed to use the I-source, V-source (7751 and 7753), and the DMM of the
Model 2790.
NOTE The schematic diagram of the 7751/7752/7753 module is provided in Section 2 of the
User’s Manual.
I-source
The programmable I-source of the 7751, 7752, and 7753 modules can be set from 0 to 50mA. The I-source is
used with the DMM of the 2790 to measure low resistance (i.e., bridgewires and shunt bars). The I-source has
a dry circuit clamp that can be used to measure oxide build-up on the contacts of a shunt bar. The dry circuit
clamp limits the test voltage at 20mV to prevent oxide piercing during the measurement.

2
V-source and I/V converter (7751/7753)
The programmable V-source of the 7751 and 7753 modules can be set from 50 to 500V. The maximum out-
put current for the 7751 V-source is 50µA for rated accuracy, while the 7753 V-source maximum output cur-
rent is 500µA for rated accuracy. When the V-source and I/V converter are used with the 2790 DMM, high
resistance measurements can be performed to test the insulation resistance of an inflator over the following
ranges:
• Model 7751: 1MΩto 1GΩ
• Model 7753: 0.1MΩto 1GΩ
The V-source can also be used as an independent voltage source. It is typically used with the 7702 module to
test multiple DUTs.
NOTE Details on using the V-source with the 7702 module are provided in Section 3 of the
Model 2790 User’s Manual.
Module wiring and installation
The 7751, 7752, and 7753 modules use screw terminals for DUT connections. The screw terminals are
accessed by removing the top cover of the module. The quick-disconnect terminal blocks can be pulled off
the PC-board to make the connections.
WARNING When connecting the DUT and before installing (or removing) the module in the main-
frame, make sure the Model 2790 is turned off, the line cord is disconnected, and there
are no external sources connected to the module or the mainframe.
CAUTION Be sure to install only 7751/7753 module covers with the integral heat sink. Also be sure
that the thermal conductive pad, located on the voltage source (Figure 1), has not been
dislodged or damaged. These thermal components are necessary to assure proper volt-
age source operation. (Note that earlier 7751 modules do not have the thermal pad or
heat sink.)
General wiring requirements
Cable wires should be mechanically durable, preferably 20AWG or larger with a high voltage insulation,
such as rubber or silicon, that are rated for at least 1000V.
NOTE Details on making connections to the 7751/7752/7753 module and installing the module
in the mainframe are provided in Section 4 of the Model 2790 User’s Manual.

3
Figure 1
Model 7751/7753 thermal conductive pad location
GUARD
SOURCE SENSE SRC
HI
SRC
HI
HI
SRC
HI
SRC
SRC
LO
SRC
LO
LO
SRC
LO
SRC
SEN
HI
SEN
HI
HI
SEN
HI
SEN
SEN
LO
SEN
LO
LO
SEN
LO
SEN
A
A
A
A
LO
I / V
GUARDISOURCEVSOURCE/ INTERLOCK
OUT
HIGNDGND HI IN LOLO
BANK 1
BANK 2
BANK 4
BANK 3
I / V
B
B
B
B
HI HI
LO LO
Thermal
Conductive
Pad
500V Supply (PS1)
Thermal Pad
Printed Circuit Board
A) Board location
B) Side view

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
7751/7752/7753 SOURCE/SWITCH MODULE SPECIFICATIONS
2790 Resistance Mode Specifications with Cards2,3
(Module function accuracy specifications are for 2 years,
23°C, ±5°C)
Source
Current
Maximum
Resistance
Typ. Open
Ckt.
Voltage
Accuracy
%Rdg + Ohms
Temperature Coefficient
(0-18°C & 28-40°C)
50mA 20Ω5.5V 0.09% + 40mΩ(0.002%+3mΩ)/°C
20mA 50Ω5.5V 0.11% + 40mΩ(0.003%+3mΩ)/°C
10mA 100Ω5.5V 0.16% + 40mΩ(0.004%+3mΩ)/°C
(Dry Circuit Ohms 1mA max with 7751, 7752, or 7753 card)
1mA 10Ω20mV 1.10% + 40mΩ(0.026%+3mΩ)/°C
(7751 Only)
Source
Voltage
Resistance
Range
Max.
Short Ckt.
Current
Accuracy
%Rdg
Temperature
Coefficient
(0-18°C & 28-40°C)
500V 10MΩ<1mA 0.8% 0.03%/°C
500V 100MΩ<1mA 1.1% 0.05%/°C
500V 1GΩ<1mA 4.0% 0.12%/°C
50V 1MΩ<1mA 1.1% 0.04%/°C
50V 10MΩ<1mA 1.1% 0.06%/°C
50V 100MΩ<1mA 1.6% 0.13%/°C
(7753 Only)
Source
Voltage
Resistance
Range
Max.
Short Ckt.
Current
Accuracy
%Rdg
Temperature
Coefficient
(0-18°C & 28-40°C)
500V 1MΩ<1mA 0.8% 0.02%/°C
500V 10MΩ<1mA 0.9% 0.03%/°C
500V 100MΩ<1mA 1.3% 0.10%/°C
500V 1GΩ<1mA 6.7% 0.27%/°C
50V 0.1MΩ<1mA 1.1% 0.03%/°C
50V 1MΩ<1mA 1.1% 0.04%/°C
50V 10MΩ<1mA 1.3% 0.11%/°C
50V 100MΩ<1mA 4.5% 0.30%/°C
Current Source Output
Output Level: Programmable 0 to 50mA (Ch. 27).
Programming Resolution: 10µA.
Output Voltage: 5.5V±10% compliance.
Accuracy: 0.06% + 10µA (2 yr Specification).
Settling Time: 1mS to 0.1% of final value (typ).
Temperature Coefficient: (0-18°C & 28-40°C)
(0.001%+0.25µA)/°C
Dry Circuit Clamp (Ch. 24): 20mV±10%, Isource ≤1mA
Voltage Source Output (7751/7753 Only)
Output Level: Programmable 50V to 500V (CH. 28).
Programming Resolution: 100mV.
Output Current: (7751) - 50µA maximum for rated accuracy, <1mA typical
into short circuit.
(7753) - 500µA maximum for rated accuracy, <1mA typical
into short circuit.
Accuracy: 0.5% + 0.13V (2yr Specification).
Settling Time: Rise Time: 50V to 500V step, 0.1% of final value,
250 ms max.
Fall Time: 500V to 50V step, 0.1% of final value,
1000 ms max.
Temperature Coefficient: (0-18°C & 28-40°C)
(0.001%+0.005V)/°C
Safety Limit: Current limited maximum current of 1mA.
Cable Discharge (Ch. 20): 100kΩShunt
Max Capacitance: 1nF
Current Measure Input (7751/7753 Only)
Range: 7751 (0-50µA), 7753 (0-500µA).
Accuracy: (7751) 0.5% (of reading) + 6nA (2yr Specification).
(7753) 0.5% (of reading) + 60nA (2yr Specification).
Temperature Coefficient: (0-18°C & 28-40°C) (0.02%+0.5nA)/°C
Voltage Burden: <1mV.
Switching Capabilities (Bank 1 – Bank 4)
4 Channels: 1 Form A switch.
8 Channels: 4 4-pole or 8 2-pole signals into DMM or I/V converter.
Contact Check: 4-Wire contact check through internal DMM.
Relay Type: Latching electromechanical.
Actuation Time: <3ms.
Contact Life (typ): >106operations at maximum source level.
>108operations cold switching.
Contact Resistance: <1 Ohm at end of contact life.
Contact Potential: <±2µV typical per contact pair, ±3µV max.
Connector Type: Plugable screw terminal, #22 AWG wire size.
Isolation Between any two Terminals1:>1GΩ, <100pF.
Isolation Between Terminals and Earth1:>1GΩ, <200pF.
Isolation Between Channel Groups1:>500GΩ, <100pF.
External Common Mode Voltage: 42V between any terminal and chassis.
(Connect no external sources.)
7751, 7752, or 7753 Module Notes
1 Isolation for channels 1-12, only one channel closed at a time, or all channels
open.
2 See User's manual for ohm specifications at sources other than those specified.
3 All specifications valid for 1 NPLC ADC aperture setting.
System Throughput
(Connect, source, measure, calculate)
0.01 NPLC, Filter Off, over GPIB Bus
High Ohms (Source V): 13 Rdgs/Sec1
Low Ohms (Source I): 9 Rdgs/Sec
1 NPLC, Filter On, Over GPIB Bus
High Ohms (Source V): 11 Rdgs/Sec1
Low Ohms (Source I): 7 Rdgs/Sec
System Throughput Notes
1. Reset upon fixed Vsource level, no settling time.

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
7751/7752/7753 SOURCE/SWITCH MODULE SPECIFICATIONS
HI
Source
Sense
Ch. 1
LO
Source
Sense
Ch. 2
A1
B1
Ch. 3
Bank 1
J101
Ch. 13
Ch. 14
Ch. 15
Ch. 16 Ch. 18
Ch. 19
HI
Inpu
LO
Sense
To Model
2790
Backplane
HI
LO
Source HI
Source LO
Sense HI
Sense LO
J105
+

50-500V
Ch. 17
HI
Source
Sense
Ch. 4
LO
Source
Sense
Ch. 5
Bank 2
J102
A2
B2
Ch. 6
HI
Source
Sense
Ch. 7
LO
Source
Sense
Ch. 8
Bank 3
J103
A3
B3
Ch. 9
HI
Source
Sense
Ch. 10
LO
Source
Sense
Ch. 11
Bank 4
J104
A4
B4
Ch. 12
In erlock
Guard
Guard
Source Enable
Isrc HI
Isrc LO
Guard
Guard
J107
Vsrc HI
Vsrc LO

+
0-50mA Ch. 24
20mV
Dry
Ck Ch. 22
Ch. 20
Ch. 23
I/V
Curren /Vol age
Amplifier
(7751/7753 Only)
Cable Discharge
(7751/7753 Only)
Vsource
Ch. 28
(7751/7753 Only)
Isource
Ch. 27
200K (7751)
20K (7753)
J106
I/V IN
I/V OUT
I/V LO
J108
100KW
1W
Ch. 21
Ch.22 Open: Isource Selec
Ch.22 Close: Vsource Selec
Ch. 25
10K
10K
+5V
In erlock
+5V

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
2790 MAINFRAME FUNCTION SPECIFICATION
MAINFRAME FUNCTION ACCURACY SPECIFICATIONS ARE FOR 1 YEAR, 23°C±5°C
DC MEASUREMENT SPECIFICATIONS1
CONDITIONS: MED (1 PLC)2or 10 PLC ACCURACY: ±(ppm of reading + ppm of range)
or MED (1 PLC) with Digital Filter of 10 (ppm = parts per million) (e.g., 10ppm = 0.001%)
Function Range Resolution
Test Current (±5%)
or Burden Voltage
Input
Resistance or
Open Ckt.
Voltage3
24 Hour4
23°C ±1°
90 Day
23°C ±5°
1 Year
23°C ±5°
Temperature Coefficient
0°-18°C & 28°-40°C
Voltage 100.0000 mV 0.1 µV >10 GΩ15 + 30 25 + 70 30 + 70 (1 + 5)/°C
1.000000 V 1.0 µV >10 GΩ15 + 6 25 + 7 30 + 7 (1 + 1)/°C
10.00000 V 10 µV >10 GΩ10 + 4 20 + 5 30 + 5 (1 + 1)/°C
100.0000 V 100 µV 10 MΩ ±1% 15 + 6 45 + 9 55 + 9 (5 + 1)/°C
1000.000 V51 mV 10 ΜΩ ±1% 20 + 6 35 + 9 50 + 9 (5 + 1)/°C
Resistance6, 8 100.0000 Ω100 µΩ1 mA 6.6 V 20 + 20 80 + 20 100 + 20 (8 + 1)/°C
1.000000 kΩ1 mΩ1 mA 6.6 V 20 + 6 80 + 6 100 + 6 (8 + 1)/°C
10.00000 kΩ10 mΩ100 µA 6.6 V 20 + 6 80 + 6 100 + 6 (8 + 1)/°C
100.0000 kΩ100 mΩ10 µA 12.8 V 20 + 6 80 + 10 100 + 10 (8 + 1)/°C
1.000000 MΩ1.0 Ω10 µA 12.8 V 20 + 6 80 + 10 100 + 10 (8 + 1)/°C
10.00000 MΩ710 ΩNote 7 7.0 V 150 + 6 200 + 10 400 + 10 (70 + 1)/°C
100.0000 MΩ7100 ΩNote 7 7.0 V 800 + 30 3000 + 30 3000 + 30 (385 + 1)/°C
Continuity (2W) 1.000 kΩ100 mΩ1 mA 6.6 V 40 + 100 100 + 100 100 + 100 (8 + 1)/°C
Current 20.00000 mA 10 nA <0.2 V 60 + 30 300 + 80 500 + 80 (50 + 5)/°C
100.0000 mA 100 nA <0.05 V 100 + 300 300 + 800 500 + 800 (50 + 50)/°C
1.000000 A 1.0 µA <0.3 V9200 + 30 500 + 80 800 + 80 (50 + 5)/°C
3.000000 A 10 µA <1.0 V9 1000 + 15 1200 + 40 1200 + 40 (50 + 5)/°C
Channel (Ratio)10 Ratio Accuracy = Accuracy of selected Channel Range + Accuracy of Paired Channel Range
Channel (Average)10 Average Accuracy = Accuracy of selected Channel Range + Accuracy of Paired Channel Range
Temperature
(Displayed in °C, °F, or K. Exclusive of probe errors.)
Range Resolution
Accuracy
1 Year (23°C ± 5°C)
Temperature Coefficient
0-18°C & 28°-40°C
4-Wire RTD:
(100Ωplatinum [PT100], D100, F100, PT385, PT3916, or user type. Offset
compensation On.)
-200°C to 630°C 0.01°C 0.06°C 0.003°C/°C
Thermistor: (2.2kΩ, 5kΩ, and 10kΩ)18
-80°C to 150°C 0.01°C 0.08°C 0.002°C/°C
DC Speed vs. Noise Rejection
Rate Filter Readings/s11 Digits
RMS Noise
10V Range NMRR CMRR13
10 50 0.01 (0.08) 6.5 < 1.2 µV 110 dB12 120 dB
1 Off 15 (12) 6.5 < 4 µV 90 dB12 120 dB
0.1 Off 500 (400) 5.5 < 22 µV – 80 dB
0.01 Off 2000 (1800) 4.5 < 150 µV – 80 dB
DC Operating Characteristics15
60Hz (50Hz) Operation
Function Digits Readings/s PLCs
6.511, 15 5 (4) 10
6.515 30 (24) 1
6.511, 15 50 (40) 1
5.511, 15 100 (80) 0.1
5.515, 16 250 (200) 0.1
5.516 480 (400) 0.1
DCV, DCI,
Ohms (<10M),
Thermistor
4.516 2000 (1800) 0.01
6.515 1.4 (1.1) 10
6.515 15 (12) 1
4W Ohms (<10M)
5.516 33 (25) 0.1
6.515 0.9 (0.7) 10
6.515 8 (6.4) 1
RTD
5.515, 16 18 (14.4) 0.1
6.515 2.5 (2) 10
6.515 15 (12) 1
Channel (Ratio),
Channel (AVG)
5.516 25 (20) 0.1

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
MAINFRAME FUNCTION SPECIFICATION
DC System Speeds14, 17
RANGE CHANGES15: 50/s (42/s).
FUNCTION CHANGES15: 50/s (42/s).
AUTORANGE TIME15: < 30ms.
ASCII READINGS TO RS-232 (19.2k BAUD): 55/s.
MAX. INTERNAL TRIGGER RATE: 2000/s.
MAX. EXTERNAL TRIGGER RATE: 375/s.
DC MEASUREMENT CHARACTERISTICS
DC Volts
A-D LINEARITY: 2.0 ppm of reading + 1.0 ppm of range.
INPUT IMPEDANCE:
100mV–10V Ranges: Selectable >10GΩ// with <400pF or
10MΩ±1%.
100V, 1000V Ranges: 10MΩ±1%.
INPUT BIAS CURRENT: <100pA at 23°C.
COMMON MODE CURRENT: <500nAp-p at 50Hz or 60Hz.
INPUT PROTECTION: Front, 1000V, Rear, 300V, 7702 card only.
Resistance
MAX 4WΩLEAD RESISTANCE: 10% of range per lead for 100Ωand
1kΩranges; 1kΩper lead for all other ranges.
OFFSET COMPENSATION: Selectable on 4WΩ, 100Ω, 1kΩ, and
10kΩranges.
CONTINUITY THRESHOLD: Adjustable 1 to 1000 Ω.
INPUT PROTECTION: Front, 1000V Source Inputs, 350V Sense
Inputs, Rear, 300V, 7702 card only.
DC Current
Shunt Resistors: 100mA–3A, 0.1Ω. 20mA, 5Ω.
Input Protection: 3A, 250V fuse.
DC Notes
1 20% overrange except on 1000V and 3A.
2
Add the following to “ppm of range” uncertainty; 100mV 15ppm, 1V
and 100V 2ppm, 100Ω30ppm, <1MΩ2ppm, 10mA and 1A 10ppm,
100mA 40ppm.
3
±2% (measured with 10MΩinput resistance DMM, >10GΩDMM on
10MΩand 100MΩranges).
4
Relative to calibration accuracy.
5
For signal levels >500V, add 0.02ppm/V uncertainty for portion
exceeding 500V.
6
Specifications are for 4-wire Ω, 100Ωwith offset compensation on.
With offset compensation on, OPEN CKT. VOLTAGE is 12.8V. For 2-
wire Ωadd 1Ωadditional uncertainty.
7 Must have 10% matching of lead resistance in Input HI and LO. Test
current +0.7µA||10MΩ
8
Add the following to “ppm of reading” uncertainty when using plug in
modules:
10 kΩ100 kΩ1 MΩ10 MΩ100 MΩ
7702, 7751, 7752 220 ppm 2200 ppm
9
Add 1V when used with plug-in modules.
10 For RATIO, DCV only. For AVERAGE, DCV only. Available with
plug-in modules only.
11 Auto zero off.
12 For LSYNC On, line frequency ±0.1 %. For LSYNC Off, use 60dB for
≥1PLC.
13 For 1kΩunbalance in LO lead.
14 Speeds are for 60Hz (50Hz) operation using factory defaults operating
conditions (*RST). Autorange off, Display off, Limits off, Trigger delay
= 0.
15 Speeds include measurements and binary data transfer out the GPIB.
16 Sample count = 1024, auto zero off.
17 Auto zero off, NPLC = 0.01.
18 For lead resistance >0Ω, add the following uncertainty/Ωfor
measurement temperatures of:
70°–100°C 100°–150°C
2.2 kΩ(44004) 0.22°C 1.11°C
5.0 kΩ(44007) 0.10°C 0.46°C
10 kΩ(44006) 0.04°C 0.19°C

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
MAINFRAME FUNCTION SPECIFICATION
AC MEASUREMENT SPECIFICATIONS1
All Ranges
Accuracy: ±(% of reading + % of range), 23°C ±5 °C
Function Range Resolution
All Ranges
Calibration Cycle
3 Hz-
10 Hz13
10 Hz-
20 kHz
20 kHz-
50 kHz
50 kHz-
100 kHz
100 kHz-
300 kHz
Voltage2100.0000 mV 0.1 µV 90 Days 0.35 + 0.03 0.05 + 0.03 0.11 + 0.05 0.6 + 0.08 4.0 + 0.5
1.000000 V 1.0 µV
10.00000 V 10 µV 1 Year 0.35 + 0.03 0.06 + 0.03 0.12 + 0.05 0.6 + 0.08 4.0 + 0.5
100.0000 V 100 µV
750.000 V 1.0 µV
(Temp. Coeff.)/°C30.035 + 0.003 0.005 + 0.003 0.006 + 0.005 0.01 + 0.006 0.03 + 0.01
3 Hz-10 Hz 10 Hz-3 kHz 3 kHz – 5 kHz
Current21.000000 A 1.0 µA 90 Day/1 Year 0.30 + 0.04 0.10 + 0.04 0.14 + 0.04
3.0000014 A 10 µA 0.35 + 0.06 0.15 + 0.06 0.18 + 0.06
(Temp. Coeff.)/°C30.035 + 0.006 0.015 + 0.006 0.015 + 0.006
(3 Hz-500 kHz) (333 ms-2 µs)
100 mV 0.333 ppm 90 Day/1 Year 80 ppm + 0.333 ppm (SLOW, 1s gate)
Frequency4
and Period to 3.33 ppm 80 ppm + 3.33 ppm (MED, 100ms gate)
750 V 33.3 ppm 80 ppm + 33.3 ppm (FAST, 10ms gate)
Additional Uncertainty ±(% of reading)
Low Frequency Uncertainty MED FAST
20Hz - 30Hz 0.3 —
30Hz - 50Hz 0 —
50Hz - 100Hz 0 1.0
100Hz - 200Hz 0 0.18
200Hz - 300Hz 0 0.10
> 300Hz 0 0
CREST FACTOR5:1–2 2–3 3–4
Additional Uncertainty: 0.05 0.15 0.30
AC MEASUREMENT CHARACTERISTICS
AC Volts
MEASUREMENT METHOD: AC-coupled, True RMS.
INPUT IMPEDANCE: 1MΩ±2% // by <100pF.
INPUT PROTECTION: 1000Vp or 400VDC, 300Vrms with 7702
module.
AC Current
MEASUREMENT METHOD: AC-coupled, True RMS.
SHUNT RESISTANCE: 0.1Ω.
BURDEN VOLTAGE: 1A <0.3Vrms, 3A <1Vrms. Add 1Vrms when
used with 7702 modules.
INPUT PROTECTION: 3A, 250V fuse.
Frequency and Period
MEASUREMENT METHOD: Reciprocal Counting technique.
GATE TIME: SLOW 1s, MED 100ms, and FAST 10ms.
AC General
AC CMRR6:70dB.
MAXIMUM CREST FACTOR: 5 at full-scale.
VOLT HERTZ PRODUCT: <= 8 × 107.
AC OPERATING CHARACTERISTICS7
60Hz (50Hz) Operation
Function Digits Readings/s Rate Bandwidth
6.582s/Reading SLOW 3 Hz-300kHz
6.581.4 (1.1) MED 30 Hz-300kHz
6.594.8 (4) MED 30 Hz-300kHz
ACV, ACI
6.5935 (28) FAST 300 Hz-300kHz
6.5 1 (1) SLOW 3 Hz-300kHz
5.5 9 (9) MED 30 Hz-300kHz
4.5 35 (35) FAST 300 Hz-300kHz
Frequency,
Period
4.510 65 (65) FAST 300 Hz-300kHz

HW 11/04/03
Rev. D
2790 SourceMeterSwitch System Specifications
MAINFRAME FUNCTION SPECIFICATION
AC System Speeds7, 11
RANGE CHANGES12: 4/s (3/s).
FUNCTION CHANGES12: 4/s (3/s).
AUTORANGE TIME: < 3s.
ASCII READINGS TO RS-232 (19.2k baud): 50/s.
MAX. INTERNAL TRIGGER RATE: 300/s.
MAX. EXTERNAL TRIGGER RATE: 250/s.
AC Notes
120% overrange except on 750V and 3A.
2Specifications are for SLOW mode and sine wave inputs >5% of range.
SLOW and MED are multi-sample A/D conversions. FAST is
DETector:BANDwidth 300 with nPLC = 1.0.
3Applies to 0°–18°C and 28°–40°C.
4Specifications are for square wave inputs only. Input signal must be
>10% of ACV range. If input is <20mV on the 100mV range then the
frequency must be >10Hz.
5Applies to non-sine waves >5Hz and <500Hz. (Guaranteed by design for
Crest Factors >4.3)
6For 1kΩunbalance in LO lead.
7Speeds are for 60Hz (50Hz) operation using factory defaults operating
conditions (*RST). Autorange off, Display off, Limits off, Trigger
delay=0. Includes measurement and binary data transfer out GPIB.
80.01% of step settling error. Trigger delay = 400ms.
9Trigger delay = 0.
10 Sample count = 1024.
11 DETector:BANDwidth 300 with nPLC = 0.01.
12 Maximum useful limit with trigger delay = 175ms.
13 Typical uncertainties. Typical represents two sigma or 95% of
manufactured units measure < 0.35% of reading and three sigma or
99.7% < 1.06% of reading.
14 For signal levels >2.2A, add additional 0.4% to “of reading” uncertainty.
Internal Scanner Speeds:
Into and Out of Memory to GPIB1
7702 Scanning DCV: 60/s
Internal Scanner Speed Notes:
1Speeds are 60Hz or 50Hz operation using factory default conditions
(*RST). NPLC = 0.01. Auto Zero off, Auto Range off, and Display off.
Sample count =1024. Includes measurement and binary data transfer out
GPIB.
GENERAL SPECIFICATIONS
POWER SUPPLY: 100V / 120V / 220V / 240V.
LINE FREQUENCY: 50Hz to 60Hz and 400Hz,
automatically sensed at power-up.
POWER CONSUMPTION: 28VA.
OPERATING ENVIRONMENT: Specified for 0°C to
50°C. Specified to 80% R.H. at 35°C. Altitude up to 2000
meters.
STORAGE ENVIRONMENT: -40°C to 70°C.
BATTERY: Lithium battery-backed memory, 3 years @
23°C.
EMC: Conforms to European Union Directive 89/336/EEC
EN61326-1.
SAFETY: Conforms to European Union Directive
73/23/EEC EN61010-1, CAT I.
VIBRATION: MIL-PRF-28800F Class 3, Random.
WARM-UP: 2 hours to rated accuracy.
DIMENSIONS:
Rack Mounting: 89mm high × 213mm wide × 370mm
deep (3.5 in. × 8.375 in. × 14.563 in.).
Bench Configuration (with handle and feet): 104mm
high × 238mm wide × 370mm deep (4.125 in. ×
9.375 in. × 14.563 in.).
SHIPPING WEIGHT: 6.5kg (14 lbs).
DIGITAL I/O: 2 inputs, 1 for triggering and 1 for
hardware interlock. 5 outputs, 4 for Reading Limits and 1
for Master Limit. Outputs are TTL compatible or can sink
250mA, diode clamped to 33V.
EARTH ISOLATION: 500Vpeak, >10GΩand <150pF
any terminal to chassis.
TRIGGERING AND MEMORY:
Window Filter Sensitivity: 0.01%, 0.1%, 1%, 10%, or
Full-scale of range (none).
Reading Hold Sensitivity: 0.01%, 0.1%, 1%, or 10% of
reading.
Trigger Delay: 0 to 99 hrs (1ms step size).
External Trigger Delay: <2ms.
External Trigger Jitter: <1ms.
Memory Size: 55,000 readings.
MATH FUNCTIONS: Rel, Min/Max/Average/Std
Dev/Peak-to-Peak (of stored reading), Limit Test, %, mX
+ b and m(1/X) +b with user defined units displayed.
REMOTE INTERFACE:
GPIB (IEEE-488.2) and RS-232C.
SCPI (Standard Commands for Programmable
Instruments)
ACCESSORIES SUPPLIED: User Manual and
Reference Manual, Screw Driver.
MODULES SUPPORTED: Models 7751, 7752, and
7702.

12/04
Specifications are subject to change without notice.
All Keithley trademarks and trade names are the property of Keithley Instruments, Inc.
All other trademarks and trade names are the property of their respective companies.
A GREATER MEASURE OF CONFIDENCE
Keithley Instruments, Inc.
Corporate Headquarters • 28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: [phone] • 1-888-KEITHLEY (534-8453) • www.keithley.com