at52bc3221a ATMEL Corporation, at52bc3221a Datasheet - Page 4

• Manufacturer Part Number: at52bc3221a
• Description: 32-mbit Flash 8-mbit Psram Stack Memory
• Manufacturer: ATMEL Corporation

32-megabit
Flash Memory
Description
Block Diagram
4
AT52BC3221A(T)
The 32-megabit Flash is a a 2.7-volt memory organized as 2,097,152 words of 16 bits each.
The memory is divided into 71 sectors for erase operations. The device has CE and OE con-
trol signals to avoid any bus contention. This device can be read or reprogrammed using a
single power supply, making it ideally suited for in-system programming.
The device powers on in the read mode. Command sequences are used to place the device in
other operation modes such as program and erase. The device has the capability to protect
the data in any sector (see “Sector Lockdown” section).
To increase the flexibility of the device, it contains an Erase Suspend and Program Suspend
feature. This feature will put the erase or program on hold for any amount of time and let the
user read data from or program data to any of the remaining sectors within the memory. The
end of a program or an erase cycle is detected by the READY/BUSY pin, Data Polling or by
the toggle bit.
The VPP pin provides data protection. When the V
erase functions are inhibited. When V
tions can be performed.
A six-byte command (Enter Single Pulse Program Mode) sequence to remove the requirement
of entering the three-byte program sequence is offered to further improve programming time.
After entering the six-byte code, only single pulses on the write control lines are required for
writing into the device. This mode (Single Pulse Word Program) is exited by powering down
the device, or by pulsing the RESET pin low for a minimum of 500 ns and then bringing it back
to V
work while in this mode; if entered they will result in data being programmed into the device. It
is not recommended that the six-byte code reside in the software of the final product but only
exist in external programming code.
CC
A0 - A20
. Erase, Erase Suspend/Resume and Program Suspend/Resume commands will not
Y-DECODER
X-DECODER
ADDRESS
BUFFER
LATCH
INPUT
OUTPUT
BUFFER
COMPARATOR
MEMORY
IDENTIFIER
I/O0 - I/O15
REGISTER
REGISTER
Y-GATING
STATUS
MAIN
DATA
PP
is at 0.9V or above, normal program and erase opera-
BUFFER
INPUT
PP
input is below 0.4V, the program and
WRITE STATE
COMMAND
REGISTER
MACHINE
PROGRAM/ERASE
VOLTAGE SWITCH
3466A–STKD–11/04
CE
WE
OE
RESET
RDY/BUSY
VPP
VCC
GND