33.6.5 Power Management

Three low-power modes are available:

  • Self-refresh mode: The SDRAM executes its own Autorefresh cycle without control of the SDRAMC. Current drained by the SDRAM is very low.
  • Powerdown mode: Autorefresh cycles are controlled by the SDRAMC. Between autorefresh cycles, the SDRAM is in powerdown. Current drained in Powerdown mode is higher than in Self-refresh Mode.
  • Deep Powerdown mode (only available with Mobile SDRAM): The SDRAM contents are lost, but the SDRAM does not drain any current.

The SDRAMC activates one low-power mode as soon as the SDRAM device is not selected. It is possible to delay the entry in Self-refresh and Powerdown modes after the last access by programming a timeout value in the SDRAMC_LPR.