SFFS948 May 2025 MSPM0L1227-Q1 , MSPM0L1228-Q1 , MSPM0L2227-Q1 , MSPM0L2228-Q1
The power management unit (PMU) generates the internally regulated core supplies for the device and provides supervision of the external supply (VDD). The PMU also contains the band gap voltage reference used individually by the PMU as well as analog peripherals. Key features of the PMU include:
The following tests must be applied for the targeted ASIL as functional safety mechanisms for this module (to provide diagnostic coverage on a specific function):
| Safety Mechanism | Description | Faults | Failure Modes |
|---|---|---|
| CPU3 | Software diversified redundancy | Targeted toward faults which can result in incorrect clock frequency (resulting in some computation failures) or failure to do a reset when required, and so forth. |
| GEN_IP_READ_STATIC_CONFIGURATION | Periodic software read back of IP static configuration registers | Targeted toward logic which is used to enable and disable IPs. If a fault results in an IP not getting enabled, the software read of the configuration registers of the IP detects such failures. |
| SYSCTL10 | External voltage monitor | This is a system-level diagnostic to detect faults on the internal LDO. |
| SYSCTL14 | Brownout voltage monitor | This is a safety mechanism which monitors the power supply to the chip and can detect undervoltage conditions early (generates an NMI). |
| SYSCTL16 | External watchdog timer | This is a system-level diagnostic which can be used to cover faults in the reset generation logic (reset asserted when not required). In general, this diagnostic covers any fault which results in incorrect program execution timing. |
| SYSCTL16 (latent fault coverage) | External watchdog timer | This mechanism (if used) can also detect faults in the MCLK monitor circuit. |
| SYSCTL8 | Brownout reset (BOR) supervisor | This is a safety
mechanism, which monitors the power supply to the chip and can detect undervoltage
conditions (generates a reset). This mechanism is triggered if the voltage falls below the specified range. |
| SYSCTL8 (latent fault coverage) | Brownout reset (BOR) supervisor | In case brownout supervisor is not functioning, this mechanism can trigger when the voltage falls below the specified range. |
| VBAT1 | VBAT supply monitor | This safety mechanism can be used to monitor the external voltage pin. |
| VBAT2 | Periodic software read of static configuration register | Targets the static configuration registers in VBAT. |