Double M33 Express

A feather-compatible development board for the LPC55S69

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This open hardware board is designed to bring more USB functionality to the feather ecosystem by taking advantage of both USB interfaces of the LPC55S69. Its high-speed interface is associated with the USB Micro-B connector, which serves as the board’s primary interface, while its full-speed interface is wired up to a USB Type-A socket footprint, on the back of the board, that can be used to attach peripherals. Both ports are device/host capable, but you may need to adapt the connectors. The LPC55S69 has plenty of internal SRAM and a second core to help it keep up with higher data rates.

We will publish all of the Double M33 Express design files after the successful completion of our crowdfunding campaign.

Flexible Power Options

We designed Double M33 Express to make life easier for anyone who’s project relies on the many capabilities of the USB standard. Since a USB host needs to provide power, we included a switching charger with reverse-boost capability. As a result, Double M33 Express can not only charge large batteries more quickly, it can generate 5 V for USB peripherals even when disconnected from a power source.

Features & Specifications

  • LPC55S69 150 MHz Dual Core Arm Cortex-M33
  • 640 KB Internal Flash
  • 320 KB SRAM
  • 8 MB SPI Flash
  • High Speed USB Micro-B connector (device/host capable)
  • Full Speed USB Type-A connector
  • MicroSD card connector
  • Qwiic / STEMMA QT / I²C connector
  • Switching charger with reverse boost
  • Two NeoPixel LEDs

See Also

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