Electronic Components Datasheet Search |
|
AM29SL400CB110ED Datasheet(PDF) 16 Page - SPANSION |
|
AM29SL400CB110ED Datasheet(HTML) 16 Page - SPANSION |
16 / 44 page 14 March 3, 2005 Ad vance Inform ati o n Figure 2. Temporary Sector Unprotect Operation Hardware Data Protection The command sequence requirement of unlock cy- cles for programming or erasing provides data pro- tection against inadvertent writes (refer to Table 5 on page 18 for command definitions). In addition, the following hardware data protection measures prevent accidental erasure or programming, which might otherwise be caused by spurious system level signals during VCC power-up and power-down transi- tions, or from system noise. Low VCC Write Inhibit When VCC is less than VLKO, the device does not ac- cept any write cycles. This protects data during VCC power-up and power-down. The command register and all internal program/erase circuits are disabled, and the device resets. Subsequent writes are ig- nored until VCC is greater than VLKO. The system must provide the proper signals to the control pins to prevent unintentional writes when VCC is greater than VLKO. Write Pulse “Glitch” Protection Noise pulses of less than 5 ns (typical) on OE#, CE# or WE# do not initiate a write cycle. Logical Inhibit Write cycles are inhibited by holding any one of OE# = VIL, CE# = VIH or WE# = VIH. To initiate a write cycle, CE# and WE# must be a logical zero while OE# is a logical one. Power-Up Write Inhibit If WE# = CE# = VIL and OE# = VIH during power up, the device does not accept commands on the ris- ing edge of WE#. The internal state machine is auto- matically reset to reading array data on power-up. Command Definitions Writing specific address and data commands or se- quences into the command register initiates device operations. Table 5 on page 18 defines the valid reg- ister command sequences. Writing incorrect ad- dress and data values or writing them in the improper sequence resets the device to reading array data. All addresses are latched on the falling edge of WE# or CE#, whichever happens later. All data is latched on the rising edge of WE# or CE#, whichever hap- pens first. Refer to the appropriate timing diagrams in the AC Characteristics section. Reading Array Data The device is automatically set to reading array data after device power-up. No commands are required to retrieve data. The device is also ready to read array data after completing an Embedded Program or Em- bedded Erase algorithm. After the device accepts an Erase Suspend com- mand, the device enters the Erase Suspend mode. The system can read array data using the standard read timings, except that if it reads at an address within erase-suspended sectors, the device outputs status data. After completing a programming opera- tion in the Erase Suspend mode, the system may once again read array data with the same exception. See “Erase Suspend/Erase Resume Commands” for more information on this mode. The system must issue the reset command to re-en- able the device for reading array data if DQ5 goes high, or while in the autoselect mode. See the Reset Command‚ on page 14 section, next. See also Requirements for Reading Array Data‚ on page 9 for more information. The Read Operations table provides the read parameters, and Figure 14‚ on page 28 shows the timing diagram. Reset Command Writing the reset command to the device resets the device to reading array data. Address bits are don’t care for this command. The reset command may be written between the se- quence cycles in an erase command sequence before erasing begins. This resets the device to reading array data. Once erasure begins, however, the de- START Perform Erase or Program Operations RESET# = VIH Temporary Sector Unprotect Completed (Note 2) RESET# = VID (Note 1) Notes: 1. All protected sectors unprotected. 2. All previously protected sectors are protected once again. |
Similar Part No. - AM29SL400CB110ED |
|
Similar Description - AM29SL400CB110ED |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |