- 1. Description
- 2. Pin Configurations
- 3. Block Diagram
- 4. Device Operation
- 5. Absolute Maximum Ratings*
- 6. DC and AC Operating Range
- 7. Operating Modes
- 8. DC Characteristics
- 9. AC Read Characteristics
- 10. AC Read Waveforms(1)(2)(3)(4)
- 11. Input Test Waveforms and Measurement Level
- 12. Output Test Load
- 13. Pin Capacitance
- 14. AC Byte Load Characteristics
- 15. AC Byte Load Waveforms
- 16. Program Cycle Characteristics
- 17. Program Cycle Waveforms(1)(2)(3)
- 18. Software Data Protection Enable Algorithm(1)
- 19. Software Data Protection Disable Algorithm(1)
- 20. Software Protected Program Cycle Waveform(1)(2)(3)
- 21. Data Polling Characteristics(1)
- 22. Data Polling Waveforms
- 23. Toggle Bit Characteristics(1)
- 24. Toggle Bit Waveforms(1)(2)(3)
- 25. Software Product Identification Entry(1)
- 26. Software Product Identification Exit(1)
- 27. Normalized ICC Graphs
- 28. Ordering Information
- 29. Packaging Information
memory (PEROM). Its 512K of memory is organized as 65,536 words by 8 bits. Man-
ufactured with Atmel's advanced nonvolatile CMOS technology, the device offers
access times to 70 ns with power dissipation of just 275 mW over the commercial tem-
perature range. When the device is deselected, the CMOS standby current is less
input voltages for programming. Five-volt-only commands determine the operation of
the device. Reading data out of the device is similar to reading from an EPROM.
Reprogramming the AT29C512 is performed on a sector basis; 128 bytes of data are
loaded into the device and then simultaneously programmed.
latched, freeing the address and data bus for other operations. Following the initiation
of a program cycle, the device will automatically erase the sector and then program
the latched data using an internal control timer. The end of a program cycle can be
detected by DATA polling of I/O7. Once the end of a program cycle has been
detected, a new access for a read or program can begin.
stored at the memory location determined by the address pins is asserted on the outputs. The
outputs are put in the high impedance state whenever CE or OE is high. This dual-line control
gives designers flexibility in preventing bus contention.
for data protection. A byte load is performed by applying a low pulse on the WE or CE input with
CE or WE low (respectively) and OE high. The address is latched on the falling edge of CE or
WE, whichever occurs last. The data is latched by the first rising edge of CE or WE.
data for the entire sector must be loaded into the device. Any byte that is not loaded during the
programming of its sector will be indeterminate. Once the bytes of a sector are loaded into the
device, they are simultaneously programmed during the internal programming period. After the
first data byte has been loaded into the device, successive bytes are entered in the same man-
ner. Each new byte to be programmed must have its high-to-low transition on WE (or CE) within
150 µs of the low-to-high transition of WE (or CE) of the preceding byte. If a high-to-low transi-
tion is not detected within 150 µs of the last low-to-high transition, the load period will end and
the internal programming period will start. A7 to A15 specify the sector address. The sector
address must be valid during each high-to-low transition of WE (or CE). A0 to A6 specify the
byte address within the sector. The bytes may be loaded in any order; sequential loading is not
required. Once a programming operation has been initiated, and for the duration of t
protection is enabled a software algorithm must be issued to the device before a program may
be performed. The software protection feature may be enabled or disabled by the user; when
shipped from Atmel, the software data protection feature is disabled. To enable the software
data protection, a series of three program commands to specific addresses with specific data
must be performed. After the software data protection is enabled the same three program com-
mands must begin each program cycle in order for the programs to occur. All software program
commands must obey the sector program timing specifications. Once set, the software data pro-
tection feature remains active unless its disable command is issued. Power transitions will not
reset the software data protection feature; however, the software feature will guard against inad-
vertent program cycles during power transitions.
start the internal write timers. No data will be written to the device; however, for the duration of
applying a low pulse on the WE or CE input with CE or WE low (respectively) and OE high. The
address is latched on the falling edge of CE or WE, whichever occurs last. The data is latched by
the first rising edge of CE or WE. The 128 bytes of data must be loaded into each sector by the
same procedure as outlined in the program section under device operation.
high inhibits program cycles; and (d) Noise filter pulses of less than 15 ns (typical) on the WE
or CE inputs will not initiate a program cycle.
accessed by hardware or software operation. The hardware operation mode can be used by an
external programmer to identify the correct programming algorithm for the Atmel product. In
addition, users may wish to use the software product identification mode to identify the part (i.e.,
using the device code), and have the system software use the appropriate sector size for pro-
gram operations. In this manner, the user can have a common board design for 256K to 4-
megabit densities and, with each density's sector size in a memory map, have the system soft-
ware apply the appropriate sector size.
The manufacturer and device code is the same for both modes.
cycle an attempted read of the last byte loaded will result in the complement of the loaded data
on I/O7. Once the program cycle has been completed, true data is valid on all outputs and the
next cycle may begin. DATA polling may begin at any time during the program cycle.
program or erase cycle. During a program or erase operation, successive attempts to read data
from the device will result in I/O6 toggling between one and zero. Once the program cycle has
completed, I/O6 will stop toggling and valid data will be read. Examining the toggle bit may begin
at any time during a program cycle.
Erase application note for details.
Maximum Ratings" may cause permanent dam-
age to the device. This is a stress rating only and
functional operation of the device at these or any
other conditions beyond those indicated in the
operational sections of this specification is not
implied. Exposure to absolute maximum rating
conditions for extended periods may affect
(including NC Pins)
with Respect to Ground ...................................-0.6V to +6.25V
with Respect to Ground .............................-0.6V to V
with Respect to Ground ...................................-0.6V to +13.5V