 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
W947D2HBJX6G Datasheet(PDF) 10 Page - Winbond |
|
||||||||||||||||||||||||||||||
W947D2HBJX6G Datasheet(HTML) 10 Page - Winbond |
|
|
10 / 60 page  W947D6HB / W947D2HB 128Mb Mobile LPDDR Publication Release Date:Jun,17, 2011 - 10 - Revision A01-003 6. FUNCTION DESCRIPTION 6.1 Initialization LPDDR SDRAM must be powered up and initialized in a predefined manner. Operations procedures other than those specified may result in undefined operation. If there is any interruption to the device power, the initialization routine should be followed. The steps to be followed for device initialization are listed below. The Mode Register and Extended Mode Register do not have default values. If they are not programmed during the initialization sequence, it may lead to unspecified operation. The clock stop feature is not available until the device has been properly initialized from Step 1 through 11. Step 1: Provide power, the device core power (VDD) and the device I/O power (VDDQ) must be brought up simultaneously to prevent device latch-up. Although not required, it is recommended that VDD and VDDQ are from the same power source. Also Assert and hold Clock Enable (CKE) to a LVCMOS logic high level Step 2: Once the system has established consistent device power and CKE is driven high, it is safe to apply stable clock. Step 3: There must be at least 200 μs of valid clocks before any command may be given to the DRAM. During this time NOP or DESELECT commands must be issued on the command bus. Step 4: Issue a PRECHARGE ALL command. Step 5: Provide NOPs or DESELECT commands for at least tRP time. Step 6: Issue an AUTO REFRESH command followed by NOPs or DESELECT command for at least tRFC time. Issue the second AUTO REFRESH command followed by NOPs or DESELECT command for at least tRFC time. Note as part of the initialization sequence there must be two Auto Refresh commands issued. The typical flow is to issue them at Step 6, but they may also be issued between steps 10 and 11. Step 7: Using the MRS command, program the base mode register. Set the desired operation modes. Step 8: Provide NOPs or DESELECT commands for at least tMRD time. Step 9: Using the MRS command, program the extended mode register for the desired operating modes. Note the order of the base and extended mode register programmed is not important. Step 10: Provide NOP or DESELECT commands for at least tMRD time. Step 11: The DRAM has been properly initialized and is ready for any valid command. |
Similar Part No. - W947D2HBJX6G |
|
Similar Description - W947D2HBJX6G |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
