SLAAEG4 October   2023 MSPM0C1104 , MSPM0L1306

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 MSPM0C Hardware Design Check List
  5. 2 Power Supplies in MSPM0C Devices
    1. 2.1 Digital Power Supply
    2. 2.2 Analog Power Supply
    3. 2.3 Built-in Power Supply and Voltage Reference
    4. 2.4 Recommended Decoupling Circuit for Power Supply
  6. 3 Reset and Power Supply Supervisor
    1. 3.1 Digital Power Supply
    2. 3.2 Power Supply Supervisor
      1. 3.2.1 Power-On Reset (POR) Monitor
      2. 3.2.2 Brownout Reset (BOR) Monitor
      3. 3.2.3 POR and BOR Behavior During Supply Changes
  7. 4 Clock System
    1. 4.1 Internal Oscillators
      1. 4.1.1 Internal Low-Frequency Oscillator (LFOSC)
      2. 4.1.2 Internal System Oscillator (SYSOSC)
    2. 4.2 External Clock Input (xFCLK_IN)
      1. 4.2.1 LFCLK_IN
      2. 4.2.2 HFCLK_IN
    3. 4.3 External Clock Output (CLK_OUT)
    4. 4.4 Frequency Clock Counter (FCC)
  8. 5 Debugger
    1. 5.1 Debug Port Pins and Pinout
    2. 5.2 Debug Port Connection With Standard JTAG Connector
      1. 5.2.1 Standard XDS110
      2. 5.2.2 Lite XDS110 (MSPM0 LaunchPad™ kit)
  9. 6 Key Analog Peripherals
    1. 6.1 ADC Design Considerations
  10. 7 Key Digital Peripherals
    1. 7.1 Timer Resources and Design Considerations
    2. 7.2 UART and LIN Resources and Design Considerations
    3. 7.3 I2C and SPI Design Considerations
  11. 8 GPIOs
    1. 8.1 GPIO Output Switching Speed and Load Capacitance
    2. 8.2 GPIO Current Sink and Source
    3. 8.3 Open-Drain GPIOs Enable 5-V Communication Without a Level Shifter
    4. 8.4 Communicate With 1.8-V Devices Without a Level Shifter
    5. 8.5 Unused Pins Connection
  12. 9 Layout Guides
    1. 9.1 Power Supply Layout
    2. 9.2 Considerations for Ground Layout
      1. 9.2.1 What is Ground Noise?
    3. 9.3 Traces, Vias, and Other PCB Components
    4. 9.4 How to Select Board Layers and Recommended Stack-up
  13. 10References

4.2.1 LFCLK_IN

To configure LFCLK to use a digital clock input, first configure the IOMUX to enable the LFCLK_IN function on the appropriate pin. When IOMUX is configured correctly and the external clock source is outputting a 32 kHz clock to LFCLK_IN, set the SETUSEEXLF bit in the EXLFCTL register in SYSCTL.

LFCLK_IN is compatible with digital square wave CMOS clock inputs and a typical duty cycle of 50% is recommanded. Check for a valid clock signal on LFCLK_IN by enabling the LFCLK monitor before setting SETUSEEXLF in the EXLFCTL register is recommanded. By default, the LFCLK monitor will check LFCLK_IN if the LFXT was not started.

Once LFCLK_IN is selected as the LFCLK source, change back to LFOSC or LFXT without going through a BOOTRST is not possible.

GUID-AB32586D-1D44-4A86-A037-C6B128E8BD16-low.png Figure 4-2 MSPM0C Series External Clock Input LFCLK_IN