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TH58NVG1S3AFT05

(14) Failure phenomena for Program and Erase operations

The device may fail during a Program or Erase operation.

The following possible failure modes should be considered when implementing a highly reliable system.

FAILURE MODE

DETECTION AND COUNTERMEASURE SEQUENIE

Block

Erase Failure

Status Read after Erase

Block Replacement

Page

Programming Failure

Status Read after Program

Block Replacement

(1) Block Verify after Program

Retry

Single Bit

Programming Failure

“ 1

to

0 “

(2) ECC

ECC :Error Correction Code .

Block Replacement

Program

Erase

When an error occurs in an Erase operation, prevent future accesses to this bad block

(again by creating a table within the system or by using another appropriate scheme).

(15) Do not turn off the power before write/erase operation is complete. Avoid using the device when the battery

is low. Power shortage and/or power failure before write/erase operation is complete will cause loss of data and/or

damage to data.

When an error happens in Block A, try to

reprogram the data into another Block (Block

B) by loading from an external buffer. Then,

prevent further system accesses to Block A ( by

creating a bad block table or by using another

appropriate scheme).

Block A

Block B

Error occurs

Buffer

memory

Figure 28.