Keithley 2700 Service Manual page 129

7702 40-Channel Differential Multiplexer
GENERAL
40 CHANNELS: 40 channels of 2-pole relay input.
All channels configurable to 4-pole.
2 CHANNELS: 2 channels of current only input.
RELAY TYPE: Latching electromechanical.
ACTUATION TIME: <3ms.
CAPABILITIES
CHANNELS 1-40: Multiplex one of 40 2-pole or one of 20 4-pole signals
into DMM.
CHANNELS 41-42: Multiplex one of 2 2-pole current signals into
DMM.
INPUTS
MAXIMUM SIGNAL LEVEL:
Channels (1-40): 300V DC or rms, 1A switched, 60W, 125VA maxi-
mum.
Channels (41-42): 60V DC or 30V rms, 3A switched, 60W, 125VA
maximum.
CONTACT LIFE (typ): >10 5 operations at max signal level.
>10 8 operations cold switching.
CONTACT RESISTANCE: <1Ω 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
ISOLATION BETWEEN ANY TERMINAL AND EARTH: >10
CROSS TALK (10MHz, 50Ω Load): <–40dB.
INSERTION LOSS (50Ω Source, 50Ω Load): <0.1dB below 1MHz.
COMMON MODE VOLTAGE: 300V between any terminal and chassis.
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: 0.5kg (1.1 lb).
Ω, <100pF.
10
Ω, <200pF.
9
<3dB below 2MHz.
HI
Card Input
LO
HI
Card Sense
LO
HI
Channel 1
LO
(Channels 2–19)
HI
Channel 20
LO
Channel 43
2-Pole (Open)
4-Pole (Closed)
(see Note)
HI
Channel 21
LO
(Channels 22–39)
HI
Channel 40
LO
3A
HI
Channel 41
LO
3A
HI
Channel 42
LO
Specifications A-9
Channel 45
(see Note)
Backplane
isolation
HI
Input
LO
Channel 44
(see Note)
Backplane
isolation
HI
Sense
To Model 2700
LO
Backplane
AMPS
NOTE Channels 43–45 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 User's Manual.
Channels 44 and 45 can be individually
controlled using ROUTe:MULTiple if the
module is not to be connected to the
internal DMM.