JS28F640P33TF70 datasheet(23/88 Pages) NUMONYX

23 / 88 page

Datasheet

Jul 2011

Order Number:208034-04

P33-65nm SBC

Read SR command (70h), which would be interpreted by the internal state machines as

Buffer Word Count.

On the next write, a word count is written to the device at the buffer address. This tells

the device how many data words will be written to the buffer, up to the maximum size

of the buffer.

On the next write, a device start address is given along with the first data to be written

to the flash memory array. Subsequent writes provide additional device addresses and

data. All data addresses must lie within the start address plus the word count.

Optimum programming performance and lower power usage are obtained by aligning

the starting address at the beginning of a 256-word boundary (A[8:1] = 0x00).

Note:

If a misaligned address range is issued during buffered programming, the program

region must also be within an 256-word aligned boundary.

After the last data is written to the buffer, the Buffered Programming Confirm command

must be issued to the original block address. The WSM begins to program buffer

contents to the flash memory array. If a command other than the Buffered

Programming Confirm command is written to the device, a command sequence error

occurs and SR[7,5,4] are set. If an error occurs while writing to the array, the device

stops programming, and SR[7,4] are set, indicating a programming failure.

When Buffered Programming has completed, additional buffer writes can be initiated by

issuing another Buffered Programming Setup command and repeating the buffered

program sequence. Buffered programming may be performed with VPP = VPPL or VPPH

(See Section 13.2, “Operating Conditions” on page 45 for limitations when operating

the device with VPP = VPPH).

If an attempt is made to program past an erase-block boundary using the Buffered

Program command, the device aborts the operation. This generates a command

sequence error, and SR[5,4] are set.

If Buffered programming is attempted while VPP is below VPPLK, SR[4,3] are set. If any

errors are detected that have set Status Register bits, the Status Register should be

cleared using the Clear Status Register command.

8.3

Buffered Enhanced Factory Programming

Buffered Enhanced Factory Programing (BEFP) speeds up flash programming. The

enhanced programming algorithm used in BEFP eliminates traditional programming

elements that drive up overhead in device programmer systems. (see Figure 33, “BEFP

Flowchart” on page 76).

BEFP consists of three phases: Setup, Program/Verify, and Exit It uses a write buffer to

spread flash program performance across 256 data words. Verification occurs in the

same phase as programming to accurately program the flash memory cell to the

correct bit state.

A single two-cycle command sequence programs the entire block of data. This

enhancement eliminates three write cycles per buffer: two commands and the word

count for each set of 256 data words. Host programmer bus cycles fill the device’s write

buffer followed by a status check. SR.0 indicates when data from the buffer has been

programmed into sequential flash memory array locations.

Following the buffer-to-flash array programming sequence, the Write State Machine

(WSM) increments internal addressing to automatically select the next 256-word array

boundary. This aspect of BEFP saves host programming equipment the address-bus

setup overhead.

JS28F640P33TF70 Datasheet(PDF) 23 Page - Numonyx B.V

JS28F640P33TF70 Datasheet(HTML) 23 Page - Numonyx B.V

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88

Datasheet Download

Link URL