Rev 1.0 | SC5507A & SC5508A
Hardware Manual
SignalCore, Inc.
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SC5507A & SC5508A Hardware Manual
Internal EEPROM
The PSG contains an EEPROM whose memory space is divided into calibration and operating data spaces.
The calibration data space contains device information such as serial number, hardware revision,
firmware revision, and production date. In addition, this space holds the calibration data for frequency
tuning and amplitude control. The operating data space contains the default startup configuration of the
device such as the single fixed tone mode frequency and sweep/list mode operation. It also holds the list
mode configuration parameters such as sweep behavior (saw or triangular waveform), software or
hardware trigger, start/stop/step frequencies, dwell time, sweep/list cycles, etc. Space is allocated for
2048 frequency points and 2048 corresponding amplitude points that the user may choose to store for
list mode operation. The internal EEPROM is not accessible for users to store data.
Modes of RF Generation
The PSG has both single fixed tone and list mode operation in frequency generation. In single fixed tone
mode, it operates as a normal synthesizer where the user writes the frequency (RF_FREQUENCY) register
to change the frequency. In list mode, the device is triggered to automatically run through a set of
frequency points that are either entered directly by the user or pre-computed by the device based on
user parameters. Configuration of the device for list mode operation is accomplished by setting up the
LIST_MODE_CONFIG register.
Sweep Function
When frequency points are generated based on the start/stop/step set of frequencies, this is (in the
context of this product) known as putting the device into sweep. When the sweep function is enabled,
the frequency points are incrementally stepped with a constant step size either in a linearly increasing or
linearly decreasing fashion.
List Function
The list function requires that the frequency points are read in from a list provided by the user. The user
will need to load the frequency points into the list buffer via the LIST_BUFFER_WRITE register, or have the
device read the frequency points from the EEPROM into it.
Sweep Direction
The sweep can be chosen to start at the beginning of a list and incrementally step to the end of the list or
vice versa.
Sweep Waveform
The list of frequency points may be swept in a sawtooth manner or triangular manner. If sawtooth is
selected, upon reaching the last frequency point the device returns back to the starting point. Plotting
frequency versus time reveals a sawtooth pattern. If triangular is selected, the device will sweep linearly
from the starting point, then reverse its direction after the last (highest or lowest) frequency and sweep
backwards toward the start point, mapping out a triangular waveform on a frequency versus time graph.