Atec Agilent-34980A - Manual (Page 9)

9
Table 2. Multiplexer selection table—specifications and characteristics*
34921A 34922A 34923A 34924A 34925A
Channels/configurations 40 2-wire 70 2-wire 80 1-wire 70 2-wire 80 1-wire
20 4-wire 35 4-wire 40 2-wire 35 4-wire 40 2-wire
4-current 20 4-wire 20 4-wire
Switch type Armature Armature Reed Reed Optically isolated FET
latching latching
Input characteristics (per channel)
Max volts ± 300 V
[1]
± 300 V
[1]
± 150 V peak
[2]
± 150 V peak
[2]
± 80 V peak
[2]
Max current (DC, AC RMS)
Switch current
1 A 1 A 0.5 A 0.5 A 0.02 A
[8]
Carry current 2 A 2 A 1.5 A 1.5 A
Power (W, VA)
[6]
60 W 60 W 10 W 10 W 1.6 W
Volt-Hertz limit 10 8 10 8 10 8 10 8 10 7
General specifications
Offset voltage
[3]
< 3 uV < 3 uV < 50 uV < 50 uV < 3 uV
< 100 uV 1-wire
Initial closed channel res
[3]
< 1.5 Ω < 1.5 Ω < 1.5 Ω [5]
< 1.5 Ω [5]
< 700 Ω
Leakage current
[3]
N/A N/A N/A N/A 20nA
[9]
T/C cold junction accuracy
[3, 10]
< 1°C N/A N/A N/A N/A
AC characteristics
Bandwidth at terminal block
[4]
45 MHz 25 MHz 45 MHz 25 MHz 1 MHz
10 MHz 1-wire
Crosstalk at terminal block (ch-ch)
[4]
300 kHz -75 dB -75 dB -75 dB -75 dB N/A
1 MHz -75 dB -75 dB -75 dB -70 dB
20 MHz -50 dB -50 dB -50 dB -45 dB
45 MHz -40 dB -40 dB
Capacitance at terminal block
HI-LO
150 pF 250 pF 130 pF 200 pF 100pF
LO – earth 150 pF 200 pF 120 pF 170 pF 300pF (600pF 1-wire)
General characteristics
Relay life, typical
No load 100 M 100 M 1000 M 1000 M N/A
10 V, 100 ma 10 M 10 M 10 M 10 M N/A
Rated load 100 k 100 k 10 k 10 k N/A
Scanning speeds
[7]
100 ch/sec 100 ch/sec 500 ch/sec 500 ch/sec 1000 ch/sec
Open/ close time, typical 4 ms/4 ms 4 ms/4 ms 0.5 ms/0.5 ms 0.5 ms/0.5 ms 0.25 ms/0.25 ms
Analog bus backplane connection Yes Yes Yes Yes Yes
[1] DC or AC RMS voltage, channel-to-channel
or channel-to-earth
[2] Peak voltage, channel-to-channel or
channel-to-earth
[3] Into analog bus. System errors are included
in the internal DMM measurement accuracy
specifications
[4] 50 Ω source, 50 Ω load, differential
measurements verified with 4-port network
analyzer (Sdd21)
[5] With in-rush resistors bypassed
[6] Limited to 6 W of channel resistance power
loss per module
[7] Speeds are for 4-1/2 digits, delay 0, display
off, autozero off, and within bank
[8] DC or peak AC current
[9] Ambient temperature < 30°C
[10] Includes temperature reference and
temperature gradient from reference to
screw terminal block. Measured under worst
case heat loading of the mainframe. For
remote mount of terminal card accuracy
consult factory.