Data Sheet

DIGITAL MULTIMETERS & SYSTEMS
www.keithley.com
1.888.KEITHLEY
(U.S. only)
A Greater Measure of Confidence
Ordering Information
7700 20-channel, Differential
Multiplexer Module
with Automatic CJC
and Screw Terminals
• 20 channels for general-
purpose measurements, plus
two channels to measure
current
• Oversize screw terminal
connection blocks are standard
for easier connections
• 50MHz bandwidth
• 300V, 1A capacity for voltage
channels; 60W, 125VA
• 3A capacity for current channels
• Low insertion loss of up to
50MHz
• Relay closures stored in
onboard memory
The Model 7700 plug-in module offers 20 chan-
nels of 2-pole or 10 channels of 4-pole multi-
plexer switching that can be configured as two
independent banks of multiplexers. There are
two additional protected channels for current
measurements. Automatic CJC is provided so
that no other accessories are required to make
thermocouple temperature measurements. In
addition, the Model 7700 contains latching
electromechanical relays that enable signal
bandwidths of up to 50MHz. The Model 7700
is ideal for RTD, thermistor, and thermocouple
temperature applications.
CAPABILITIES
CHANNELS 1-20: Multiplex one of 20 2-pole or one of 10 4-pole
signals into DMM.
CHANNELS 21-22: Multiplex one of 2 2-pole current signals
into DMM.
INPUTS
MAXIMUM SIGNAL LEVEL:
Channels (1-20): 300V DC or 300V rms (425V peak) for
AC waveforms, 1A switched, 60W, 125VA maximum.
Channels (21-22): 60V DC or 30V rms, 3A switched, 60W,
125VA maximum.
CONTACT LIFE (typ.): >10
5
operations at max. signal level.
>10
8
operations no load
1
.
1
Open thermocouple detector on during thermocouple measurements.
Minimum signal level 10mV, 10µA.
CONTACT RESISTANCE: <1W at end of contact life.
CONTACT POTENTIAL: <±500nV typical per contact, 1µV max.
<±500nV typical per contact pair,
1µV max.
OFFSET CURRENT: <100pA.
CONNECTOR TYPE: Screw terminal, #20 AWG wire size.
ISOLATION BETWEEN ANY TWO TERMINALS: >10
10
W,
<100pF.
ISOLATION BETWEEN ANY TERMINAL AND EARTH: >10
9
W,
<200pF.
INSERTION LOSS (50W Source, 50W Load):
w/Internal DMM w/o Internal DMM*
<0.1 dB: 1 MHz 1 MHz
<3 dB: 2 MHz 50 MHz
CROSSTALK (50W Load):
w/Internal DMM w/o Internal DMM*
10 MHz: <–40 dB <–40 dB
25 MHz: ** <–25 dB
COMMON MODE VOLTAGE: 300V or 300V rms (425V peak) for
AC waveforms between any terminal and chassis.
TEMPERATURE ACCURACY USING INTERNAL CJC:
1.0°C (see mainframe specification for details).
* Channels 24 and 25 are open. Refer to ROUTe:MULTiple command in
27XX User Manual.
** Not valid.
GENERAL
20 CHANNELS: 20 channels of 2-pole relay input. All channels
configur able to 4-pole.
2 CHANNELS: 2 channels of current only input.
RELAY TYPE: Latching electromechanical.
ACTUATION TIME: <3ms.
FIRMWARE: Specified for Model 2700 rev. A01, 2701 rev. A01,
and 2750 rev. A01 or higher.
ENVIRONMENTAL
OPERATING ENVIRONMENT: Specified for 0°C to 50°C.
Specified to 80% R.H. at 35°C.
STORAGE ENVIRONMENT: –25°C to 65°C.
WEIGHT: 0.45kg (1 lb).
ACCESSORY AVAILABLE: Model 7401 Type K Thermocouple
Wire, 30.5m (100 ft).
Cold junction
Ref x3
Channel 1
HI
LO
Channel 10
HI
LO
(Channels 2–9)
Channel 11
HI
LO
Channel 20
HI
LO
(Channels 12–19)
Channel 21
HI
LO
Channel 22
HI
LO
AMPS
HI
LO
Sense
HI
LO
Input
Channel 23
2-Pole (Open)
4-Pole (Closed)
(see Note)
3A
3A
To Model 2700,
2701, or 2750
Backplane
Channel 25
(see Note)
Backplane
isolation
Channel 24
(see Note)
Backplane
isolation
NOTE:Channels 23–25 in this schematic
refer to the designations used for
control and not actual available channels.
For more information, refer to the
ROUTe:MULTiple command section
in the Model 2700, 2701, or 2750 User’s Manual.
Channels 24 and 25 can be individually
controlled using ROUTe:MULTiple if the
module is not to be connected to the
internal DMM.
Card
AMPS
LO
Card Sense
HI
LO
Card Input
HI
LO
Cold junction
Ref x3
7700
20-channel, Differential Multiplexer Module
with Automatic CJC, Screw Terminals, and up to 50MHz Bandwidth
SERVICES AVAILABLE
7700-3Y-EW 1-year factory warranty extended to 3 years
from date of shipment
Use with Integra Series mainframes: 2700, 2701, 2750 Use with Integra Series mainframes: 2700, 2701, 2750