Rev 1.0 | SC5507A & SC5508A
Hardware Manual
SignalCore, Inc.
10
SC5507A & SC5508A Hardware Manual
Table 4. Pinout of the SC5508A USB communication connector.
PIN #
USB Function
Description
1
VBUS
Vcc (+5 Volts)
2
D-
Serial Data (neg)
3
D+
Serial Data (pos)
4
ID
Not Used
5
GND
Device Ground (also tied to connector shell)
Reset Button (Pin Hole)
Behind this pin hole is the reset button
that’s
only available on the SC5508A. Using a pin to lightly depress
this momentary-action push button switch will cause a hard reset to the device, putting it back to its
default settings. All user settings will be lost. System reset capability can also be accessed through the
communication header connector.
3
Theory and Operation
The PSG is an instrument-grade, high performance synthesizer with easy to program register-level
control. It functions as a standard synthesized CW source with the added capability of a sweep/list mode
that makes it ideal for applications ranging from automated test systems to telecommunication
equipment to scientific research labs. Being small and modular, it is the ideal solution for system
integration applications that require a high performance RF source. In addition, it could be used as a
general-purpose lab source. Figure 3 shows the block diagram of the device, and the following sub-
sections provide details of its operation.
Figure 3. PSG block diagram
N
Fine Step
Gen
REF
IN
REF
OUT
RF
OUT
2. 9 GHz
–
GHz
Sum Gen
Harmonic
Coarse
St ep Gen
DC-
50MHz
Gen
SENSOR
IN
VCXO
10
OCXO
25 MHz to 6.25 G Hz path
ALC
controller
Filt er
Bank
ADC
0
1
ADC
RMS
ENV
DC to 50 MHz pat h
VVA
VVA
60 dB
DSA
32 dB
DSA
HF ALC
DAC
LF
DAC
FracN
Coarse
St ep Gen