K4M51323PC Datasheet, PDF (11/12 Pages) Samsung semiconductor – Mobile-SDRAM

K4M51323PC-S(D)E/G/C/F
Mobile-SDRAM
Partial Array Self Refresh
1. In order to save power consumption, Mobile SDRAM has PASR option.
2. Mobile SDRAM supports 3 kinds of PASR in self refresh mode : Full array, 1/2 of full array, 1/4 of full array
BA1=0 BA1=0
BA0=0 BA0=1
BA1=0 BA1=0
BA0=0 BA0=1
BA1=0 BA1=0
BA0=0 BA0=1
BA1=1 BA1=1
BA0=0 BA0=1
BA1=1 BA1=1
BA0=0 BA0=1
BA1=1 BA1=1
BA0=0 BA0=1
- Full Array
- 1/2 Array
- 1/4 Array
Temperature Compensated Self Refresh
Partial Self Refresh Area
Note :
1. In order to save power consumption, Mobile-SDRAM includes the internal temperature sensor and control units to control the
self refresh cycle automatically according to the two temperature range ; 45 °C and 85 °C(for Extended) / 70 °C(for Commercial).
2. If the EMRS for external TCSR is issued by the controller, this EMRS code for TCSR is ignored.
3. It has +/- 5 °C tolerance.
Self Refresh Current (IDD6)
Temperature Range
-E/C
-G/F
Unit
Full Array 1/2 Array 1/4 Array Full Array 1/2 Array 1/4 Array
45 °C^*3
85/70 °C
300
270
255
250
220
205
uA
600
500
450
500
400
350
B. POWER UP SEQUENCE
1. Apply power and attempt to maintain CKE at a high state and all other inputs may be undefined.
- Apply VDD before or at the same time as VDDQ.
2. Maintain stable power, stable clock and NOP input condition for a minimum of 200us.
3. Issue precharge commands for all banks of the devices.
4. Issue 2 or more auto-refresh commands.
5. Issue a mode register set command to initialize the mode register.
6. Issue a extended mode register set command to define DS or PASR operating type of the device after normal MRS.
For operating with DS or PASR, set DS or PASR mode in EMRS setting stage.
In order to adjust another mode in the state of DS or PASR mode, additional EMRS set is required but power up sequence is not
needed again at this time. In that case, all banks have to be in idle state prior to adjusting EMRS set.
February 2006