
Rev 1.1 | SC5317A & SC5318A
Hardware Manual
SignalCore, Inc.
10
SC5317A & SC5318A Hardware Manual
•
The Power Conditioning and Digital Control Board contains the supply switcher that generates
the needs rails for the RF modules and an onboard MCU that provides both the computation
engine and interface between the user and the RF modules.
The figure below shows how the modules relate to each other.
Figure 3. Simplified Block Representation of the Downconverter Assembly Module
The downconverter has only a single conversion stage that converts the RF signal to an intermediate
frequency (IF) stage. The input range of this downconverter is from 6 GHz to 26.5 GHz, while the output
IF range is from 50 MHz to 3000 MHz. The LO signal can be selected from the internal synthesizer or an
external signal generator. The frequency accuracy and stability of the internal LO is derived from an
onboard TCXO with accuracy of better than 500 ppb. For better accuracy and stability, the synthesizer can
lock to an external reference of higher precision.
The Signal Chain
The conversion module contains the mixers, filters, amplifiers, and attenuators used to convert, purify,
and maintain the amplitude of the signal, all the way from the input of the device to its output. This
cascade of signal conversion and conditioning stages is often referred to as the signal chain, which is
shown on the system block drawing of the next figure.
The RF Input
All RF connectors are SMA types rated to 26.5 GHz of operation. The RF port is AC coupled with a 0.1
𝑢𝐹
broadband capacitor as indicated in the next figure. The input frequency range at this port is less than 6
GHz to greater than 26.5 GHz. The upper limit to which the device tunes to above 26.5 GHz varies slightly
from unit to unit depending on the limits of the oscillator circuitry. The usability of the upper out-of-
bounds region depends on the roll-off response of the mixer.
Signal Conversion
Synthesized Local Oscillator
Supply Conditioning and Digital Control/Interface
RF Input
LO/Ref
Front
Digital IO
Supply
IF Output
LO Rear
RF Bypass
Out