3.6.3 LDO Selection/Bypass Header
The ATSAMR30M Sensor Board operates with supply voltage ranging from 1.8V(1) to 3.63V. Low Dropout Regulator (LDO) selection/bypass header (J4) is used to select/bypass the LDO based on the need for 3.3V supply.
Jumper positions for the following modes of power supply:
- LDO Bypass mode(2) – Place the jumper cap between pins (1 and 2) of J4
- LDO Selection mode(3) – Place the jumper caps between pins (1 and 3) and pins (2 and 4) of J4 as shown in Figure 2-1.
Note:
- If the CryptoAuthentication™ device (ATECC608A) is mounted on the board, the minimum supply voltage required to operate it is 2V.
- LDO Bypass mode can be used to avoid LDO current consumption for extending the battery life. This is the preferred mode if the ATSAMR30M Sensor Board is supplied with a 3V battery or 3.3V from a Click Board (FTDI Click Board).
- LDO Selection mode can be used if the ATSAMR30M Sensor Board supplies power to the connected Click Board, which needs 3.3V to operate.