- The Block Protect (BP1, BP0) bits allow part or entire
of the memory to be configured as read-only.
Hardware Data Protection
- Write Protect (WP#) pin will inhibit write operations
to the status register
• Page Program (up to 256 Bytes)
- Typical 2 ms per page program time
• Sector, Block and Chip Erase
- Typical 40 ms sector/block/chip erase time
Single Cycle Reprogramming for Status Register
- Build-in erase before programming
High Product Endurance
- Guarantee 100,000 program/erase cycles per single
sector (preliminary)
- Minimum 20 years data retention
Industrial Standard Pin-out and Package
- 8-pin JEDEC SOIC
- 8-contact WSON
- Optional lead-free (Pb-free) packages
GENERAL DESCRIPTION
The Pm25L V512/010 are 512 Kbit/1 Mbits 3.0 V olt-only serial Flash memories. These devices are designed to use
a single low voltage, range from 2.7 Volt to 3.6 Volt, power supply to perform read, erase and program operations.
The devices can be programmed in standard EPROM programmers as well.
The device is optimized for use in many commercial applications where low-power and low-voltage operation are
essential. The Pm25L V512/010 is enabled through the Chip Enable pin (CE#) and accessed via a 3-wire interface
consisting of Serial Data Input (Sl), Serial Data Output (SO), and Serial Clock (SCK). All write cycles are completely self-timed.
Block Write protection for top 1/4, top 1/2 or the entire memory array (1M) or entire memory array (512K) is enabled
by programming the status register. Separate write enable and write disable instructions are provided for additional
data protection. Hardware data protection is provided via the WP pin to protect against inadvertent write attempts
to the status register. The HOLD pin may be used to suspend any serial communication without resetting the serial
sequence.
The Pm25L V512/010 are manufactured on PMC’s advanced nonvolatile CMOS technology, P-FLASH™. The devices are offered in 8-pin JEDEC SOIC and 8-contact WSON packages with operation frequency up to 25 MHz.
Pm25L V512/010 can be driven by a microcontroller on the SPI bus as shown in Figure 1. The serial communication
term definitions are in the following section.
MASTER: The device that generates the serial clock.
SLA VE: Because the Serial Clock pin (SCK) is always an input, the Pm25L V512/010 always operates as a slave.
TRANSMITTER/RECEIVER: The Pm25L V512/010 has separate pins designated for data transmission (SO) and
receptio n (S l).
MSB: The Most Significant Bit (MSB) is the first bit transmitted and received.
SERIAL OP-CODE: After the device is selected with CE# going low, the first byte will be received. This byte
contains the op-code that defines the operations to be performed.
INV ALID OP-CODE: If an invalid op-code is received, no data will be shifted into the Pm25L V512/010, and the serial
output pin (SO) will remain in a high impedance state until the falling edge of CE# is detected again. This will
reinitialize the serial communication.
Figure 1. Bus Master and SPI Memory Devices
SDO
SPI Interface with
(0, 0) or (1, 1)
Bus Master
CS3 CS2 CS1
Note: 1. The Write Protect (WP#) and Hold (HOLD#) si
SDI
SCK
SCKSOSI
SPI Memory
Device
CE#WP# HOLD#HOLD#HOLD#
SCK SOSISCK SOSI
SPI Memory
Device
CE#WP#CE#WP#
nals should be driven, High or Low as appropriate.
The Pm25L V512/010 is designed to interface directly with the synchronous serial peripheral interface (SPI) of the
6800 type series of microcontrollers.
The Pm25LV512/010 utilizes an 8-bit instruction register. The list of instructions and their operation codes are
contained in Table 1. All instructions, addresses, and data are transferred with the MSB first and start with a highto-low transition.
Write is defined as program and/or erase in this specification. The following commands, P AGE PROGRAM,
SECTOR ERASE, BLOCK ERASE, CHIP ERASE, and WRSR are write instructions for Pm25L V512/010.
READ PRODUCT ID (RDID): The RDID instruction allows the user to read the manufacturer and product ID of the
device. The instruction code is followed by three dummy bytes, each bit being latched-in on Serial Data Input (SI)
during the rising edge of Serial Clock (SCK). Then the first manufacturer ID (9Dh) is shifted out on Serial Data
Output (SO), followed by the device ID (7Bh = Pm25L V512; 7Ch = Pm25LV010) and the second manufacturer ID
(7Fh), each bit been shifted out during the falling edge of Serial Clock (SCK).
WRITE ENABLE (WREN): The device will power up in the write disable state when Vcc is applied. All write
instructions must therefore be preceded by the WREN instruction.
WRITE DISABLE (WRDI): T o protect the device against inadvertent writes, the WRDI instruction disables all write
commands. The WRDI instruction is independent of the status of the WP# pin.
READ ST ATUS REGISTER (RDSR): The RDSR instruction provides access to the status register. The READY/
BUSY and write enable status of the device can be determined by the RDSR instruction. Similarly, the Block Write
Protection bits indicate the extent of protection employed. These bits are set by using the WRSR instruction.
During internal write cycles, all other commands will be ignored except the RDSR instruction.
WRITE ST A TUS REGISTER (WRSR): The WRSR instruction allows the user to select one of four levels of protection for the Pm25L V010. The Pm25L V010 is divided into four blocks where the top quarter (1/4), top half (1/2), or all
of the memory blocks can be protected (locked out) from write. The Pm25L V512 is divided into 2 blocks where all
of the memory blocks can be protected (locked out) from write. Any of the locked-out blocks will therefore be READ
only . The locked-out block and the corresponding status register control bits are shown in Table 5.
The three bits, BP0, BP1, and WPEN, are nonvolatile cells that have the same properties and functions as the
regular memory cells (e.g., WREN, RDSR).
The WRSR instruction also allows the user to enable or disable the Write Protect (WP#) pin through the use of the
Write Protect Enable (WPEN) bit. Hardware write protection is enabled when the WP# pin is low and the WPEN bit
is "1". Hardware write protection is disabled when either the WP# pin is high or the WPEN bit is "0." When the
device is hardware write protected, writes to the Status Register, including the Block Protect bits and the WPEN
bit, and the locked-out blocks in the memory array are disabled. Write is only allowed to blocks of the memory
which are not locked out. The WRSR instruction is self-timed to automatically erase and program BP0, BP1, and
WPEN bits. In order to write the status register, the device must first be write enabled via the WREN instruction.
Then, the instruction and data for the three bits are entered. During the internal write cycle, all instructions will be
ignored except RDSR instructions. The Pm25LV512/010 will automatically return to write disable state at the
completion of the WRSR cycle.
Note: When the WPEN bit is hardware write protected, it cannot be changed back to "0", as long as the WP# pin
READ: Reading the Pm25LV512/010 via the SO (Serial Output) pin requires the following sequence. After the CE#
line is pulled low to select a device, the READ instruction is transmitted via the Sl line followed by the byte address
to be read (Refer to Table 7). Upon completion, any data on the Sl line will be ignored. The data (D7-D0) at
the specified address is then shifted out onto the SO line. If only one byte is to be read, the CE# line should be
driven high after the data comes out. The READ instruction can be continued since the byte address is automatically incremented and data will continue to be shifted out. For the Pm25L V512/010, when the highest address is
reached, the address counter will roll over to the lowest address allowing the entire memory to be read in one
continuous READ instruction.
FAST_READ: The device is first selected by driving CE# low. The F AST READ instruction is followed by a 3-byte
address (A23-A0) and a dummy byte, each bit being latched-in during the rising edge of SCK (Serial Clock). Then
the memory contents, at that address, is shifted out on SO (Serial Output), each bit being shifted out, at a
maximum frequency fFR, during the falling edge of SCK (Serial Clock).
The first byte addressed can be at any location. The address is automatically incremented to the next higher
address after each byte of data is shifted out. When the highest address is reached, the address counter will roll
over to the lowest address allowing the entire memory to be read with a single FAST READ instruction. The FAST
READ instruction is terminated by driving CE# high.
PAGE PROGRAM (PG_PROG): In order to program the Pm25LV512/010, two separate instructions must be
executed. First, the device must be write enabled via the WREN instruction. Then the P AGE PROGRAM instruction can be executed. Also, the address of the memory location(s) to be programmed must be outside the protected address field location selected by the Block Write Protection Level. During an internal self-timed programming cycle, all commands will be ignored except the RDSR instruction.
The P AGE PROGRAM instruction requires the following sequence. After the CE# line is pulled low to select the
device, the P AGE PROGRAM instruction is transmitted via the Sl line followed by the address and the data (D7-D0)
to be programmed (Refer to Table 7). Programming will start after the CE# pin is brought high. The low-to-high
transition of the CE# pin must occur during the SCK low time immediately after clocking in the D0 (LSB) data bit.
The READY/BUSY status of the device can be determined by initiating a RDSR instruction. If Bit 0 = 1, the program
cycle is still in progress. If Bit 0=0, the program cycle has ended. Only the RDSR instruction is enabled during the
program cycle. A single PROGRAM instruction programs 1 to 256 consecutive bytes within a page if it is not write
protected. The starting byte could be anywhere within the page. When the end of the page is reached, the address
will wrap around to the beginning of the same page. If the data to be programmed are less than a full page, the data
of all other bytes on the same page will remain unchanged. If more than 256 bytes of data are provided, the address
counter will roll over on the same page and the previous data provided will be replaced. The same byte cannot be
reprogrammed without erasing the whole sector/block first. The Pm25LV512/010 will automatically return to the
write disable state at the completion of the PROGRAM cycle.
Note: If the device is not write enabled (WREN) the device will ignore the Write instruction and will return to the
standby state, when CE# is brought high. A new CE# falling edge is required to re-initiate the serial
SECTOR_ERASE, BLOCK_ERASE: Before a byte can be reprogrammed, the sector/block which contains the
byte must be erased. In order to erase the Pm25L V512/010, two separate instructions must be executed. First, the
device must be write enabled via the WREN instruction. Then the SECTOR ERASE or BLOCK ERASE instruction
can be executed.
The BLOCK ERASE instruction erases every byte in the selected block if the block is not locked out. Block
address is automatically determined if any address within the block is selected. The BLOCK ERASE instruction
is internally controlled; it will automatically be timed to completion. During this time, all commands will be ignored,
except RDSR instruction. The Pm25L V512/010 will automatically return to the write disable state at the completion
of the BLOCK ERASE cycle.
CHIP_ERASE: As an alternative to the SECTOR and BLOCK ERASE, the CHIP ERASE instruction will erase
every byte in all blocks that are not locked out. First, the device must be write enabled via the WREN instruction.
Then the CHIP ERASE instruction can be executed. The CHIP ERASE instruction is internally controlled; it will
automatically be timed to completion. The CHIP ERASE cycle time maximum is 100 miliseconds. During the
internal erase cycle, all instructions will be ignored except RDSR. The Pm25L V512/010 will automatically return to
the write disable state at the completion of the CHIP ERASE.
HOLD: The HOLD# pin is used in conjunction with the CE# pin to select the Pm25L V512/010. When the device is
selected and a serial sequence is underway, HOLD# pin can be used to pause the serial communication with the
master device without resetting the serial sequence. T o pause, the HOLD# pin must be brought low while the SCK
pin is low. To resume serial communication, the HOLD# pin is brought high while the SCK pin is low (SCK may still
toggle during HOLD). Inputs to the Sl pin will be ignored while the SO pin is in the high impedance state.
HARDWARE WRITE PROTECT: The Pm25LV512/010 has a write lockout feature that can be activated by asserting the write protect pin (WP#). When the lockout feature is activated, locked-out sectors will be READ only. The
write protect pin will allow normal read/write operations when held high. When the WP# is brought low and WPEN
bit is "1", all write operations to the status register are inhibited. WP# going low while CE# is still low will interrupt
a write to the status register. If the internal status register write cycle has already been initiated, WP# going low will
have no effect on any write operation to the status register. The WP# pin function is blocked when the WPEN bit in
the status register is "0". This will allow the user to install the Pm25L V512/010 in a system with the WP# pin tied
to ground and still be able to write to the status register. All WP# pin functions are enabled when the WPEN bit is
set to "1".
1. Stresses under those listed in “Absolute Maximum Ratings” may cause permanent damage
to the device. This is a stress rating only. The functional operation of the device or any other
conditions under those indicated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating condition for extended periods may affected
device reliability.
2. Maximum DC voltage on input or I/O pins are VCC + 0.5 V. During voltage transitioning
period, input or I/O pins may overshoot to VCC + 2.0 V for a period of time up to 20 ns.
Minimum DC voltage on input or I/O pins are -0.5 V. During voltage transitioning period,
input or I/O pins may undershoot GND to -2.0 V for a period of time up to 20 ns.