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Radio Board v2

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Status: Completed


  • One design, two applications
    • Application 1: Radio for Control board
    • Application 2: Standalone wireless sensor
  • Provide a radio for the Control Board
  • Standalone MCU with RF for home automation
  • Dash7, if suitable, for general interest (too complex for now)
    • CC430F5137 is supported by OpenTag M2 though.

Related docs


Radio board v2 gerbers
Radio board v2 3D view in Kicad
Radio board v2 schema


Ref Value Digikey ref Mouser ref
C1, C3, C5, C6, C8, C10, C11, C14, C15, C22 100nF 490-1318-1-ND GRM155R61A104KA01D
C2 470nF 445-4989-1-ND C1005X5R1A474K
C4 10 uF 445-1371-1-ND C2012Y5V1A106Z
C7, C9 30 pF 445-4902-1-ND C1005C0G1H300J
C12, C13 2 pF 445-4862-1-ND C1005C0G1H020B
C16, C18 3.9 pF 490-1272-1-ND GRM1555C1H3R9CA01D !=DK
C17, C21 220 pF 490-1293-1-ND GRM1555C1H221JA01D
C19 8.2 pF 445-4892-1-ND C1005C0G1H8R2C
C20 5.6 pF 490-3103-1-ND GJM1555C1H5R6CB01D
L1, L2, L4 27 nH 490-2628-1-ND LQG15HS27NJ02D
L3 22 nH 490-2627-1-ND LQG15HS22NJ02D
R1 56 kΩ 311-56.0KLRCT-ND RC0402FR-0756KL
R2, R3 4.7 kΩ 311-4.7KJRCT-ND AC0402JR-074K7L !=DK
R4 47 kΩ 311-47.0KLRCT-ND C0402FR-0747KL
U1 CC430F5137 296-25330-5-ND CC430F5137IRGZ
X1 26 MHz 535-11297-1-ND ABM3C-26000MHZ-D4Y-T
CN1, CN2 2mm header N/A N/A
CN4 antenna N/A N/A

Application 1: Control Board Radio

Provide fast long range radio communication between two Control boards or between a Control Board and a standalone MCU with RF.


  • CC430F5137 with 433MHz (4K ram, 32K flash)
  • TMP275 not assembled on the board
  • Same socket as xBee, 2x 10pin with 2mm pitch
  • Power pins
  • Spy by wire
  • UART pins
  • SPI
  • Radio can wake up control board via WAKE-UP pin
  • Control board can wake up radio via several GPIOs

Application 2: Standalone wireless sensor

Provide a very low power wireless temperature sensor.


  • CC430F5137 with 433MHz (4K ram, 32K flash)
  • TMP275 assembled on the board
  • No regulators, no charging
  • Needs SW for monitoring input voltage and to sleep if below specified threshold
  • Sleeps >99% of time for power saving
  • Extra GPIO and analog pins for other use cases than the TMP275


  1. Temperature range of cc430 and the crystal is only -40°C - +85°C. +105°C upper limit would be better for sauna.
  2. SMA antenna bottom side ground pads covered by solder mask
  3. A debug LED could be convenient.