Void Lake Fusion 4 (VLF4)

SRAD Avionics from the McMaster Rocketry Team

Our Avionics Museum

Selling point

• Pyro short circuit protection
• Molex nano-fit connectors
• 1W LoRa, 100km+ LoS range
• GPS + IMU + baro sensor fusion, reducing the chance of ejecting prematurely
• Modern 3D visualizer
• Small
• Open source firmware
• Relatively cheap

Pyro

• 3 pyro channels, each 8A continuous (current limited by the connector due to size)
• pyro channels not connected to battery+ when not firing (unlike raven)
• continuity detection
• short circuit protection

Sensors

• MCU: STM32H723
• IMU 1: ±2000deg/s ±16g (LSM6DSMTR)
• IMU 2: ±100g (H3LIS100DLTR)
• Magnetometer: MMC5603NJ
• Barometer: max altitude 30km (MS5607)
• Storage: 64MB NOR Flash (W25Q512JVFIQ)
• GPS: L80RE-M37
• Radio: 1W LoRa (e22-900m30s)

Connectivity

• 2 buzzers for stereo sound
• usb type-c
• battery: 2 pin molex nano-fit
• power & arming switch: 4 pin molex nano-fit (no large current is carried over switches)
• pyro: 6 pin molex nano-fit
• extension: 8 pin molex nano-fit:
  • ground: 1 pin
  • power out (battery voltage) (only provides power out if the power switch is turned on): 1 pin
  • serial: 2 pins
  • CAN: 2 pins
  • GPIO: 2 pins
• Serial Wire Debug: 5 pin molex pico-clasp
• SMA antenna connector

Software (WIP, to be open sourced)

• Async embedded rust

JLCPCB Manufacturing Specifications

• Base Material: FR-4

• Layers: 6

• PCB Thickness: 1.6

• Impedance Control: yes JLC06161H-3313

• PCB Color: Black

• Silkscreen: White

• Material Type: FR-4 TG155

• Via Covering: Epoxy Filled & Capped

• Surface Finish: ENIG

• Gold Thickness: 1 U"

• Deburring/Edge rounding: No

• Outer Copper Weight: 1 oz

• Inner Copper Weight: 0.5 oz

• Gold Fingers: No

• Flying Probe Test: Fully Test

• Castellated Holes: no

• Remove Order Number: Specify a location

• Min via hole size/diameter: 0.2mm/(0.3/0.35mm)

• 4-Wire Kelvin Test: Yes

• Paper between PCBs: No

• Appearance Quality: IPC Class 2 Standard

• Confirm Production file: Yes

• Silkscreen Technology: Ink-jet/Screen Printing Silkscreen

• X-out board: Accept

• Package Box: With JLCPCB logo

• Board Outline Tolerance: ±0.2mm(Regular)