For energy harvesting applications, the best energy modes are typically EM2 and EM4. These modes allow the EFR32xG22E to consume minimal power when idle:
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EM2 : The device retains its RAM contents. Low-energy peripherals that use the low-frequency oscillator (LFXO or ULFRCO) remain active. These include LETIMER, I2C, EUART, and others.
It’s ideal when the device needs to wake frequently or maintain context with minimal energy usage. -
EM4 : EM4 provides the lowest current consumption of all energy modes. Uses less power and is ideal when your device can stay asleep for long periods. Ordinary RAM is not retained, but 128 bytes of Backup RAM (BURAM) can be preserved.
However, it requires more energy and time to wake up and reinitialize the device. Use EM4 when wake-up frequency is low and ultra-low power is critical.
Picking the right mode depends on how often your device wakes up and how much energy you have available.
Applicable Part Number
| DigiKey Part Number | Manufacturer Part Number |
|---|---|
| 336-SLWSTK6021A-ND | SLWSTK6021A |
| 336-SLWRB4183A-ND | SLWRB4183A |
| 336-XG27-DK2602A-ND | XG27-DK2602A |
| 336-XG21-PK6026A-ND | XG21-PK6026A |
| 336-XG27-PK6017A-ND | XG27-PK6017A |
| 336-SLWRB4182A-ND | SLWRB4182A |
| 336-SLWRB4181C-ND | SLWRB4181C |
| 336-SLWRB4181B-ND | SLWRB4181B |
| 336-XG26-PK6028A-ND | XG26-PK6028A |
| 336-XG22-EK2710A-ND | XG22-EK2710A |
| 336-XG27-RB4194A-ND | XG27-RB4194A |
| 336-XG24-RB4187C-ND | XG24-RB4187C |
| 336-XG24-RB4186C-ND | XG24-RB4186C |
| 336-XG24-RB4198A-ND | XG24-RB4198A |
| 336-XG21-PK6027A-ND | XG21-PK6027A |
| 336-XG24-PK6036A-ND | XG24-PK6036A |
| 336-XG24-RB4188A-ND | XG24-RB4188A |
| 336-XG21-RB4196B-ND | XG21-RB4196B |
| 336-XG21-RB4195B-ND | XG21-RB4195B |
| 336-XG26-RB4118A-ND | XG26-RB4118A |
| 336-BG27-RB4110B-ND | BG27-RB4110B |
| 336-BG27-RB4111B-ND | BG27-RB4111B |
| 336-XG24-RB4115B-ND | XG24-RB4115B |
| 336-XG27-PK6018A-ND | XG27-PK6018A |
| 336-XG27-PK6019A-ND | XG27-PK6019A |
| 336-XG24-DK2606A-ND | XG24-DK2606A |
| 336-SLWRB4180B-ND | SLWRB4180B |
| 336-XG22-RB4415A-ND | XG22-RB4415A |
| 336-XG22-EK8200A-ND | |
| XG22-EK8200A | |
| 336-XG22-EK8200A |