2.1 VDDSDMMC power supply over-consumption
The SAMA5D2 SiP devices listed in the table below exhibit an over-consumption of roughly 5 mA on the VDDSDMMC power rail.
| Affected Devices |
|---|
| ATSAMA5D225C-D1M |
| ATSAMA5D27C-D1G |
| ATSAMA5D28C-D1G |
Work around
Even if the SDMMCs are not used, the following procedure greatly reduces the over-consumption on VDDSDHC:
- Enable the peripheral clock by setting the clock for the SDHC
- PMC_PCER0.PID31 = 1
- Launch an SDMMC calibration by setting the bits EN and ALWYSON in the
SDMMC_CALCR register
- SDMMC0_CALCR = SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN
- Wait for the end of calibration by polling the EN bit while (SDMMC0_CALCR & SDMMC_CALCR_EN);
- Disable the SDMMC peripheral clock for the SDHC
- PMC_PCDR0.PID31 = 1
With this procedure, the power consumption is reduced from ~5mA to 90μA.