SLAZ345AF October   2012  – May 2021 MSP430F6731

 

  1. 1Functional Advisories
  2. 2Preprogrammed Software Advisories
  3. 3Debug Only Advisories
  4. 4Fixed by Compiler Advisories
  5. 5Nomenclature, Package Symbolization, and Revision Identification
    1. 5.1 Device Nomenclature
    2. 5.2 Package Markings
      1.      PZ100
      2.      PN80
    3. 5.3 Memory-Mapped Hardware Revision (TLV Structure)
  6. 6Advisory Descriptions
    1. 6.1  ADC39
    2. 6.2  ADC42
    3. 6.3  ADC69
    4. 6.4  AUXPMM1
    5. 6.5  AUXPMM2
    6. 6.6  BSL7
    7. 6.7  BSL14
    8. 6.8  CPU21
    9. 6.9  CPU22
    10. 6.10 CPU36
    11. 6.11 CPU40
    12. 6.12 CPU46
    13. 6.13 CPU47
    14. 6.14 DMA4
    15. 6.15 DMA7
    16. 6.16 DMA9
    17. 6.17 DMA10
    18. 6.18 EEM8
    19. 6.19 EEM17
    20. 6.20 EEM19
    21. 6.21 EEM23
    22. 6.22 JTAG26
    23. 6.23 JTAG27
    24. 6.24 LCDB5
    25. 6.25 LCDB6
    26. 6.26 PMM7
    27. 6.27 PMM11
    28. 6.28 PMM12
    29. 6.29 PMM14
    30. 6.30 PMM15
    31. 6.31 PMM18
    32. 6.32 PMM20
    33. 6.33 PMM26
    34. 6.34 PORT15
    35. 6.35 PORT19
    36. 6.36 SD3
    37. 6.37 UCS11
    38. 6.38 USCI36
    39. 6.39 USCI37
    40. 6.40 USCI41
    41. 6.41 USCI42
    42. 6.42 USCI47
    43. 6.43 USCI50
  7. 7Revision History

6.5 AUXPMM2

AUXPMM Module

Category

Functional

Function

Latch-up in AUXPMM

Description

Latch-up current can appear at the AUXPMM module supply pins in the following two scenarios:

Scenario 1: When the AUXPMM is configured for hardware- or software-controlled switching and the module switches from DVCC to AUXVCC2, latch-up current can appear at AUXVCC2 at the switching point defined by SVSMHCTL.SVSMHRRL (or AUXCTL2.AUX0LVLx). The probability for this event to occur depends on:
a) Operating temperature (higher temperatures increase probability)
b) External AUXVCC2 voltage level (higher voltages increase probability)
c) SVSMHRRL level (lower levels increase probability) defining the switching level in hardware-controlled mode
d) AUX0LVLx level (lower levels increase probability) defining the switching level in software-controlled mode (applicable to DVCC only)

Scenario 2: When a battery is connected to DVCC, AUXVCC1 or AUXVCC2 as the first voltage supply, due to the low internal resistance of the battery a very fast rise time is seen by the AUXPMM and latch-up current can appear at the connected supply if:
a) Rise times are in the range of 140 kV/s (faster rise times increase probability)
b) Device operates at temperatures of 75 deg C and above (higher temperatures increase probability)

The latch-up current disappears after complete power cycles of all supply sources.

Workaround

For scenario 1:
- Increase SVSMRRL to a level above maximum external voltage expected on AUXVCC2. SVSMRRL = 6 or 7 (requires VCORE level of 3) is applicable for AUXVCC2 of up to maximum voltage, 3.58V, while a lower SVSMRRL setting can be selected if a lower voltage (e.g. 3.3V) is expected on AUXVCC2.

Or

- Connect all 3 supplies via 3 external diodes to DVCC and realize the switching externally without using the internal AUXPMM switches. See application report "Implementation of a Three-Phase Electronic Watt-Hour Meter Using the MSP430F471xx" for details.

Or

- Use AUXVCC1 instead of AUXVCC2 for backup supply

For scenario 2:
Limit the supply voltage ramp up time through a series resistor (e.g. 10 Ohm) in the critical supply path. Side effects such as voltage dips due to high current consumption of the device need to be considered.