Aeroflex Circuit Technology

SCD1667 REV A 4/28/97 Plainview NY (516) 694-6700

11

Bus

Operations

Command

Sequence

Comments

Standby

Write

Erase

Read

Data Polling to Verify Erasure

Standby

Compare Output to FFH

Figure 4

Erase Algorithm

Start

Erasure Completed

Write Erase Command Sequence

(See Below)

Data Poll or Toggle Bit

Successfully Completed

Chip Erase Command Sequence

(Address/Command)

Individual Sector/Multiple Sector

(Address/Command)

Erase Command Sequence

5555H/AAH

2AAAH/55H

5555H/80H

5555H/AAH

2AAAH/55H

5555H/10H

5555H/80H

5555H/AAH

2AAAH/55H

5555H/AAH

2AAAH/55H

Sector Address/30H

Sector Address/30H

Sector Address/30H

Additional Sector

Erase Commands

are Optional

Note 1. To Ensure the command has been accepted, the system software should check the

status of D3 prior to and following each subsequent sector erase command. If D3 were high on

the second status check, the command may not have been accepted.