Other Parts Discussed in Thread: TMS320C5515
Hi,
I am trying to reduce power consumption in a system build around a TMS320C5515 with an external microSDRAM (Micron MTH4M16LF)
The power consumtion for the SDRAM behaves in a strange way. When running a memorytest without using any EMIF power management (i.e constant reading/writing) the current just increase a few mA. With no ext.memory access the current is 4mA@1.8V. With memoryaccess the current is 7mA@1.8V
If I activate SelfRefresh (SDCR2=0x8001) I got a current of 200uA with no access but 30mA during read/write.
With powerdown plus refresh (SDCR2 = 0x6001) I got a current of 400uA with no access but 18mA during read/write.
The EMIF itself behaves in a simular way:
Without PM the current to the EMIF is 7mA
With SelfRefresh the current is 9mA
With powerdown activated the current is 9mA
With no memory access the EMIF supplycurrent is 5mA in all SDRAM PM modes.
The meassurements have been done by a diff. probe connected to a oscilloscope.
The measurements have been done on a EVM 5515 from SpectrumDigital
Question: Is it normal with increasing read/write current when activating the Selfrefresh or Powerdown.
Regards
David