SLAAEO9 October   2024 MSPM0C1103 , MSPM0C1103-Q1 , MSPM0C1104 , MSPM0C1104-Q1 , MSPM0G1105 , MSPM0G1106 , MSPM0G1107 , MSPM0G1505 , MSPM0G1506 , MSPM0G1507 , MSPM0G1519 , MSPM0G3105 , MSPM0G3105-Q1 , MSPM0G3106 , MSPM0G3106-Q1 , MSPM0G3107 , MSPM0G3107-Q1 , MSPM0G3505 , MSPM0G3505-Q1 , MSPM0G3506 , MSPM0G3506-Q1 , MSPM0G3507 , MSPM0G3507-Q1 , MSPM0G3519 , MSPM0L1105

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1MSPM0 Low Power Mode Introduction
    1. 1.1 MSPM0 Power Domain Introduction
    2. 1.2 MSPM0 Low-Power Mode Introduction
    3. 1.3 Power Consumption Measurement Based on EnergyTrace
      1. 1.3.1 EnergyTrace Introduction
      2. 1.3.2 EnergyTrace Configuration With CCS
  5. 2MSPM0 System Power Consumption Measurement
  6. 3MSPM0 Peripheral Power Consumption Measurement
    1. 3.1  GPIO
    2. 3.2  RTC
    3. 3.3  WWDT
    4. 3.4  TIMER
      1. 3.4.1 TIMG0
      2. 3.4.2 TIMA0
    5. 3.5  UART
    6. 3.6  I2C
    7. 3.7  SPI
    8. 3.8  MCAN
    9. 3.9  SYSPLL
    10. 3.10 VREF
    11. 3.11 ADC
  7. 4Low-Power Mode Guidance

3.6 I2C

Table 3-8 I2C Power Consumption Test Table
I2C Configuration Current
Hardware
  • Not connect the target I2C device
  • 2.2k pullup resister in SCL and SDA pin
Software
  • I2C work as controller, I2C clock source from MCLK, and work frequency is 400kHz;
Test condition Enable I2C power and initial, WFI (STANDBY1) 1.20mA
Disable I2C Async Fast Clock Request, WFI (STANDBY1) 2.5uA
I2C continuously transfer data(400kHz) 3.72mA
RUN0 mode, while (1) {} 2.41mA
Close I2C power, while (1) {} 2.18mA
Enter low-power mode, WFI (STANDBY1) 2.0uA

I2C Power Consumption Test Under STANDBY1 Mode

Figure 3-7 I2C Power Consumption Test Under STANDBY1 Mode

According the test result above, there are several conclusions and tips about I2C in low-power mode:

  • I2C module enable power in this case at RUN0 mode is about 230uA
  • Reset I2C or disable power can both close I2C power
  • When I2C power is enabled and MCU goes into STOP or STANDBY mode, Asynchronous Fast Clock Request occurs, resulting in over 1mA current power consumption. A way to completely disable the Asynchronous Fast Clock Request function of I2C is by adding instruction I2C_INST->GPRCM.CLKCFG = (1<<8) | (0xA9 << 24), where I2C_INST is I2C register base address.

If I2C is not reset before entering STOP or STANDBY mode, the configuration restores after exit of low-power mode. And I2C can work normally by enable power.