Specifications

22
HP 44478A/B
Description
The HP 44478A/B multiplexer module is an ideal choice
for broadband switching of high frequency or fast pulse
signals. Dual 1-to-4 mulitplexers provide bi-directional
switching of signals from DC to 1.3 GHz. High channel
isolation (>55 dB @ 1 GHz) assures quality dynamic-
range measurements using spectrum, network, or
distortion analyzers. Each 1-to-4 multiplexer consists of
7 relays in a "tree" structure, which provides high
isolation and low VSWR (voltage standing wave ratio).
All the connectors on the module's edge are female
BNC for ease of wiring. Off-channels can be terminated
in resistors to maintain proper operation of DUT
circuitry. Simply plug a 50/75 Ω SMB type resistive
termination onto the on-board male SMB connector
provided for each channel.
Specifications
Input Characteristics
Maximum Scan Rate: 43 ch/ sec
Maximum Voltage: 42V, DC+AC peak
Maximum Current: 1A
Maximum Power: Per channel 24W, 24VA or 44dBm
Characteristic Impedance: 44478A 50 Ω
44478B 75 Ω
DC Performance
Thermal Offset: <6µV (<2µV, Typ.)
Initial Closed Channel Resistance: <1 Ω
Insulation Resistance
(between terminals):
<(25°C, 40% RH) >10
10
Ω
Capacitance:
Center-Center <0.006pF
Center-Shield <60pF
Rise Time: <300psec
Signal Delay: <3nsec
AC Performance 10MHz 100MHz 500 MHz 1.3GHz
Insertion Loss ≤(40°C, 95% RH) <0.3dB <0.7dB <1.5dB <3.0dB
≤(25°C, 40% RH) <0.2dB <0.5dB <1.1dB <1.9dB
Crosstalk
Channel-Channel, Channel-Common <-90dB <-80dB <-65dB <-55dB
Group-Group, Module-Module <-90dB <-80dB <-70dB <-60dB
VSWR <1.20 <1.25 <1.35 <1.55
Dual 1 x 4 RF Multiplexer (1.3 GHz, 50/75Ω)
• Switching up to 1 A, 24 W or 24 VA
• Insertion loss less than 1.9 dB @1.3 GHz
HP 44478A/B
HP 44478A typical
performance diagram
HP 44478B typical performance diagram