One way Siglent achieved this design milestone was to use one single board to implement all of the scope’s analog and digital circuitry. However, 8- or 10-layer pcbs are expensive, so Siglent needed to minimize that single board’s size and one way to do that is to really chop the component count on the board. To do that without cutting functions, you need to use the most highly integrated devices you can find, which is probably why Siglent’s design engineers selected the Xilinx Zynq Z-7020 SoC as the keystone for this DSO’s digital section. As discussed yesterday, the use of the Zynq Z-7020 SoC allowed Siglent’s design team to introduce advanced features from the company’s high-end DSOs and put them into these entry-level DSOs with essentially no increase in BOM cost.
Here’s a screen capture from Dave’s new teardown video showing you what the new Siglent DSO’s main board looks like. That’s Dave’s finger poised over the Xilinx Zynq SoC (under the heat sink), which is flanked to the left and right by the two Samsung K4B1G1646I 1Gbit (64Mx16) DDR3 SDRAM chips used for waveform capture and the display buffer—among other things.
As discussed yesterday, the Zynq SoC’s two on-chip ARM Cortex-A9 processors can easily handle the scope’s GUI and housekeeping chores. Its on-chip programmable logic implements the capture buffer, the complex digital triggering, and the high-speed computation needed for advanced waveform math and the 1M-point FFT. Finally, the Zynq SoC’s programmable I/O and SerDes transceiver pins make it easy to interface to the scope’s high-speed ADC and the DDR3 memory needed for the deep, 14M-point capture buffer and the display memory for the DSO’s beautiful color LCD with 256 intensity levels. (All this is discussed in yesterday’s Xcell Daily blog post about these new DSOs.)
Here’s a photo of that Siglent screen from one of Dave’s previous videos, where he uses a prototype of this Siglent DSO to troubleshoot and fix a malfunctioning HP 54616B DSO that had been dropped:
Note: Since sending this prototype to Dave, Siglent has apparently decided to bump the bandwidth of these DSOs to 200MHz. Just another reminder of how competitive this entry-level DSO market has become, and how the Zynq SoC's competitive advantages can be leveraged in a system-level design.