技术资料.pdf - 第23页
23 34945A/34 945EXT Microwave S witch/Attenua tor Driver This modu le allows you to control sw itches, attenuat ors, and other dev ices ext ernal t o the 34 980A. T he 34945A / 34 945E XT provid es the power and contro l…
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DC to 3 GHz
DC to 26.5 GHz
3
34941A
34942A
34946A
34947A
Channels
quad 1x4
quad 1x4
2 SPDT
3 SPDT
Switch Type
50 Ω unterminated,
latching relays
75 Ω unterminated,
latching relays
50 Ω terminated 50 Ω unterminated
RF characteristics
Frequency range
2
DC to 3 GHz DC to 1.5 GHz
DC to 4 GHz,
20 GHz or 26.5 GHz
DC to 4 GHz,
20 GHz or 26.5 GHz
Insertion loss
2
< 40C/80% RH)
100 MHz
1 GHz
3 GHz
0.15 dB
0.60 dB
1.40 dB
0.15 dB
0.60 dB
N/A
DC to 4 GHz < 0.42 dB,
@ 20 GHz < 0.69 dB,
@ 26.5 GHz < 0.8 dB
DC to 4 GHz < 0.42 dB,
@ 20 GHz < 0.69 dB,
@ 26.5 GHz < 0.8 dB
VSWR
100 MHz
1 GHz
3 GHz
1.03
1.25
1.55
1.15
1.35
N/A
DC to 4 GHz < 1.15,
@ 20 GHz < 1.30,
@ 26.5GHz < 1.6
DC to 4 GHz < 1.15,
@ 20 GHz < 1.30,
@ 26.5GHz < 1.6
Isolation (dB)
2
100 MHz
1 GHz
3 GHz
Contact factory
80 dB
58 dB
40 dB
Contact factory
80 dB
60 dB
N/A
DC to 4 GHz > 85 dB,
@ 20 GHz > 67 dB,
@ 26.5 GHz > 60 dB
DC to 4 GHz > 85 dB, @
20 GHz > 67 dB,
@ 26.5 GHz > 60 dB
Spurious noise below 1.3 GHz
-140 dBm
-140 dBm
80 dB
80 dB
Rise time
< 80 ps
< 160 ps
N/A
N/A
Signal delay
< 1 ns
< 1 ns
N/A
N/A
Capacitance
< 30 pF
< 30 pF
N/A
N/A
Switching characteristics
Max volts
1
30 V
30 V
7 VDC
7 VDC
Max current
0.5 A
0.5 A
N/A
N/A
Max power
10 W
5
10 W
5
1 W@7 VDC,50 W peak
4
1 W@7 VDC,50 W peak
4
Offset voltage
10 µV
10 µV
N/A
N/A
Initial channel resistance
6
1 Ω
1 Ω
N/A
N/A
Volt-Hertz limit
2 x 10
10
2 x 10
10
General characteristics
Relay life
300,000 at 30 V/10 mA
load; 100,000 at 10 W
load RF SAmeas
300,000 at 30 V/10 mA
load; 100,000 at 10 W load
RF SAmeas
> 5 M cycles > 5 M cycles
Open/close time
18 ms/18 ms
18 ms/18 ms
< 15 ms/15 ms
< 15 ms/15 ms
Connector type
Female SMA
Mini 75 Ω SMB
Female SMA
Female SMA
Coil voltage
N/A
N/A
24 VDC
24 VDC
Analog bus backplane
connection
No No No No
Note:
1. Channel-to-earth
2. 50 Ω source, 50 Ω load (75 Ω for 34942A)
3. For more detailed switch specifications, see the Keysight N1810TL, N1811TL, N1812UL for 34946A, and N1810UL
for the 34947A.
4. 10 usec maximum duration
5. Max power is 1 W between 30 MHz and 1 GHz for CISPR 11 compliance
6. Channel resistance is typically < 1.5 Ω but can go as high as 50 Ω when a channel is used in measurement
applications with < 10 mA load current. Increased relay channel resistance for measurements with load currents
below 10 mA can occur on cards that have been out of service or following relay inactivity for periods of greater
than 1 week. Switching relays for 2K cycles prior to use may reduce the variation in channel resistance. Applies to
the 34941A and 34942A.
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34945A/34945EXT Microwave Switch/Attenuator
Driver
This module allows you to control switches, attenuators, and other devices external to the 34980A. The
34945A / 34945EXT provides the power and control signals for many of the most popular microwave
switches and attenuators. One 34945A /34945EXT combination can drive up to 64 switch coils—that’s 32
standard SPDT switches. The 34945A /EXT can be extended by adding additional 34945EXT boards.
The first 34945EXT is powered by the mainframe. You can add up to seven additional 34945EXT boards
with user-supplied power. Multiple switch operations are performed in sequential order, or for faster,
simultaneous switching, you can connect an external power supply to the 34945EXT.
The Y1150A-Y1155A distribution boards enable simple connections to the external switches. The
distribution boards plug onto the 34945EXT and are used to route the power and control signals from the
driver module to the switches using standard cables.
The 34945A /34945EXT also has sensing capabilities that allow a read back of the actual position of the
switch or attenuator. Drive signals for LED indicators are also provided to give a visual indication of the
switch position. The following microwave switches and attenuators are supported by the Y1150AY1155A
distribution boards:
•
N181x/U9397x series SPDT switches
•
8762/3/4 series SPDT switches (screw terminals)
•
8765x coaxial switches
•
8766x/8767x/8768x multiport switches
•
87104x/106x/L710xx/L720xx multiport switches
•
87406x series matrix switches
•
87204x/206x series multiport switches
•
87606x series matrix switches
•
87222x/L7222 transfer switches
•
849x and 8490x series attenuators
•
Other switches and devices through individual screw terminal connections
Figure 16. 34945A/34945EXT
24
34945EXT switch drive (64 channels, low side drive mode)
General specifications
Driver off voltage (max)
30 V
Driver off leakage current
500 μA
Driver on current (max)
600 mA
Driver on voltage (max)
0.5 V @ 600 mA
34945EXT switch drive (64 channels, TTL drive mode)
Hi output voltage
3 V @ Iout = 2 mA
Lo output voltage
0.4 V @ Iin = 20 mA
Lo input Current
20 mA
34945EXT position indicator sense inputs
Channels
64
Lo input voltage (max)
0.8 V
Hi input voltage (min)
2.5 V
Input resistance
> 100 kΩ @ Vin ≤ 5 V
> 20 kΩ @ Vin > 5 V
Maximum input voltage
30 V
34945EXT switch drive power supply (34945EXT powered by 34945A)
Voltage
24 V nominal (external power supply required for switches needing more than
24 V)
Current
100 mA continuous + 200 mA (15 msec pulse, 25% duty cycle)
34945EXT external power connection
Voltage range
4.75 V to 30 V
Current limit
2 A
LED indicator (Current mode divers)
Channels
64
Supply voltage
5 V nominal
LED drive current
5 mA nominal, (prog 1-20 mA)
Driver compliance voltage
0.8 V
34945EXT dimensions
Dimensions
11.2" x 4.5" x 1.5" high with distribution boards installed
Maximum of eight 34945EXT’s per mainframe
Switch drive control is also available in L4445A and L4490A/91A RF Switch Platform.
Note: See Configuration Guide, “34945A, L4445A, L4490A/L4491A” literature number 5989-2272EN, for configuration details.