Deep Sleep Mode

Materials

  • AMB82-mini x 1

  • Optional: Push button x 1

  • Optional: Register 220 ohms x 1

Example

In this example, the development board will demo the Deep Sleep Mode for power save. There are 3 wake-up sources for Deep Sleep Mode which are: AON Timer, AON GPIO, and RTC. The system will count down 5s then go to Deep Sleep mode. Upon the wake-up source being tiggered, the system will be reboot and wake up again.

The module and board power consumption report under Deep Sleep mode are listed in these two tables below.

RTL8735B module power consumption test results

Wake-up source

Module power consumption (uA)

Deep Sleep Mode (measure at 3V3)

AON timer

32.78

AON GPIO

40.98

RTC

41.08

AMB82 MINI board Power Consumption

Wake-up source

Development board power consumption Approximate measurement (mA)

Normal Mode

Standby Mode

AON timer

53.01

4.59

AON GPIO

52.97

4.74

RTC

53.05

4.65

Open example in “File” -> “Examples” -> “AmebaPowerMode” -> “DeepSleepMode”.

image01

Next is setting up the system and entering the power mode. Please refer to the following steps for entering Deep Sleep mode.
Step 1. Set up the “WAKEUP_SOURCE”, AON timer: 0; AON GPIO: 1; RTC: 2.
Step 2. Set up the wake-up source setting. There are 3 wake-up sources, each one has its own settings.
For AON timer, at section ”#if (WAKEUP_SOURCE == 0)”, set value to “CLOCK” and “SLEEP_DURATION”. “CLOCK” can be 4MHz or 100kHz. “SLEEP_DURATION” unit is in seconds.
For AON GPIO, at section “#elif (WAKEUP_SOURCE == 1)”, set value to “WAKUPE_SETTING”. “WAKUPE_SETTING” in this case is the Pin number, that can be 21 or 22. The GPIO pin is set to active high, please refer to the following connection.

image02

For RTC, at section “#elif (WAKEUP_SOURCE == 2)”, set value to “ALARM_DAY”, “ALARM_HOUR”, “ALARM_MIN”, or “ALARM_SEC”. All alarm values set the duration of RTC wake-up. The range is “1day, 0h, 0m, 0s” to “365day, 23h, 59min, 59s”.
Step 3. Start the Deep Sleep mode. There is only 1 optional setting for this step. When the wake-up source is set to RTC, use “PowerMode.start(1970, 1, 1, 0, 0, 0);” to replace “PowerMode.start();” for setting the start time. (Default is 1970.1.1 00:00:00).

image03

To wake up, all timers will automatically wake up when the duration is finished, all GPIO pins must active high by pressing the push button.
The correct boot, enter deep sleep, and reboot cycle will be same as following picture.

image04