PMC
Pm39F010 / Pm39F020 / Pm39F040
DEVICE OPERATION (CONTINUED)
HARDWARE DATA PROTECTION
CHIP ERASE
Hardware data protection protects the devices from un-
intentional erase or program operation. It is performed
in the following ways: (a) VCC sense: if VCC is below 3.8
V (typical), the write operation is inhibited. (b) Write
inhibit: holding any of the signal OE# low, CE# high, or
WE# high inhibits a write cycle. (c) Noise filter: pulses
of less than 5 ns (typical) on the WE# or CE# input will
not initiate a write operation.
The entire memory array can be erased through a chip
erase operation. Pre-programs the devices are not
required prior to a chip erase operation. Chip erase starts
immediately after a six-bus-cycle chip erase command
sequence. All commands will be ignored once the chip
erase operation has started. The devices will return to
standby mode after the completion of chip erase.
SECTOR AND BLOCK ERASE
The memory array of Pm39F010/020/040 are organized
into uniform 4 Kbyte sectors. A sector erase operation
allows to erase any individual sector without affecting
the data in others. The memory array of those devices
are also organized into uniform 64 Kbyte blocks (sector
group - consists of sixteen adjacent sectors). A block
erase operation allows to erase any individual block. The
sector or block erase operation is similar to chip erase.
Table 1. Product Identification
I/O7 DATA# POLLING
Product Identification
Manufacturer ID
Device ID:
Data
The Pm39F010/020/040 provide a Data# Polling feature
to indicate the progress or completion of a program and
erase cycles. During a program cycle, an attempt to
read the devices will result in the complement of the last
loaded data on I/O7. Once the program operation is com-
pleted, the true data of the last loaded data is valid on all
outputs. During a sector, block, or chip erase cycle, an
attempt to read the device will result a “0” on I/O7. After
the erase operation is completed, an attempt to read
the device will result a “1” on I/O7.
9Dh
Pm39F010
1Ch
4Dh
4Eh
Pm39F020
Pm39F040
I/O6 TOGGLE BIT
The Pm39F010/020/040 also provide a Toggle Bit fea-
ture to detect the progress or completion of a program
and erase cycles. During a program or erase cycle, an
attempt to read data from the device will result a tog-
gling between “1” and “0” on I/O6. When the program or
erase operation is complete, I/O6 will stop toggling and
valid data will be read. Toggle bit may be accessed at
any time during a program or erase cycle.
Issue Date: March, 2004, Rev: 1.3
Programmable Microelectronics Corp.
8
PMC [ PMC-SIERRA, INC ]
