ppboards - shields for the DE10-Nano board

ppboards are shields that plug into the two 40-pin 2.54 mm GPIO pin headers on the DE10-Nano board. They enable custom interfacing of the FPGA module with the external world. As an example, a KiCad design for a simple shield using PMOD-style expansion connectors is provided (PP_PMOD, described below). This reference design can be used as is or it can serve as a starting point for user customization (different connectors, buffering, etc.).

PP_PMOD

This PulsePins shield board provides output signals broken out on four dual PMOD-style ports carrying 8 bits each. In addition, the board has expansion connectors for trigger inputs and AUX signals, separate header breakouts for trigger control and status, and dedicated SMA connectors for clocking and instrument hookup. Other features:

  • all signals on connectors have ESD protection diodes
  • SMA connectors for external clock and for pulse-per-second (PPS) signals; monitoring LED for PPS signal; optional built-in 50-ohm terminators (enabled by jumpers)
  • SMA connector for one trigger signal; it is connected to a fast comparator with a tunable threshold voltage; optional 50-ohm terminator; monitoring LED
  • two buffered output signals are wired to SMA connectors; monitoring LEDs
  • Status LEDs: trigger armed, trigger activated, done, buffer error
  • Activity & heartbeat LEDs
  • Qwiic I2C connector for external modules
  • Optional onboard MCP9808 temperature monitor (I2C interface)
  • Optional 16-bit DAC (I2C interface) with separate low-noise power supply (a possible application is frequency tuning of an OCXO; in combination with the PPS input from a GPS receiver, PulsePins can serve as a simple GPSDO)
  • Footprints for optional CMOS oscillator modules for clocking the PulsePins system
  • Testpoints for troubleshooting
  • GND connection bars for grounding oscilloscope probes

PP_PMOD ppboard

Detailed board documentation:

KiCad schematics and PCB layouts, as well as the Gerber files for producing the boards, are available on the GitHub repository.