Texas Instruments MSP430F6723, Руководство пользователя

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and
1. Ensure the SVSx, SVMx are configured to prevent the issue from occurring by the
following:
- Configure the SVSL module for slow wake up (SVSLFP = 0). Note that this will increase
the wakeup time from LPM2/3/4 to twakeupslow (~150 us).
or
- Do not configure the SVSH/SVMH such that the modules transition from Normal mode
to an OFF state on LPM entry and ensure SVSH/SVMH is in manual mode. Instead
force the modules to remain ON even in LPMx. Note that this will cause increased power
consumption when in LPMx.
Refer to the MSP430 Driver Library( MSPDRIVERLIB ) for proper PMM configuration
functions.
Use the following function, PMM15Check (void), to determine whether or not the existing
PMM configuration is affected by the erratum. The return value of the function is 1 if the
configuration is affected, and 0 if the configuration is not affected.
unsigned char PMM15Check (void)
{
// First check if SVSL/SVML is configured for fast wake-up
if ( (!(SVSMLCTL & SVSLE)) || ((SVSMLCTL & SVSLE) && (SVSMLCTL & SVSLFP)) ||
(!(SVSMLCTL & SVMLE)) || ((SVSMLCTL & SVMLE) && (SVSMLCTL & SVMLFP)) )
{ // Next Check SVSH/SVMH settings to see if settings are affected by PMM15
if ((SVSMHCTL & SVSHE) && (!(SVSMHCTL & SVSHFP)))
{
if ( (!(SVSMHCTL & SVSHMD)) || ((SVSMHCTL & SVSHMD) &&
(SVSMHCTL & SVSMHACE)) )
return 1; // SVSH affected configurations
}
if ((SVSMHCTL & SVMHE) && (!(SVSMHCTL & SVMHFP)) && (SVSMHCTL &
SVSMHACE))
return 1; // SVMH affected configurations
}
return 0; // SVS/M settings not affected by PMM15
}
}
2. If fast servicing of interrupts is required, add a 150us delay either in the interrupt
service routine or before entry into LPM3/LPM4.
PMM18
PMM Module
Category
Functional
Function PMM supply overvoltage protection falsely triggers POR
Description The PMM Supply Voltage Monitor (SVM) high side can be configured as overvoltage
protection (OVP) using the SVMHOVPE bit of SVSMHCTL register. In this mode a POR
should typically be triggered when DVCC reaches ~3.75V.
If the OVP feature of SVM high side is enabled going into LPM234, the SVM might trigger
at DVCC voltages below 3.6V (~3.5V) within a few ns after wake-up. This can falsely
www.ti.com Advisory Descriptions
SLAZ340AF – OCTOBER 2012 – REVISED MAY 2021
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MSP430F6723 Microcontroller 19
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