M29W800DB-70N1

The M29W800DB-70N1 is an 8 megabit 3V dual-organization NOR Flash memory from STMicroelectronics offering both 8-bit byte and 16-bit word configurations via the BYTE# pin. When BYTE# is high, the device operates in 16-bit word mode (512K words of 16 bits); when low, it operates in 8-bit byte mode (1M bytes of 8 bits). This dual-organization feature provides design flexibility, allowing the same memory device to be used across different system architectures. The bottom boot block architecture places boot and parameter blocks at the low address range, with a total of 19 blocks (1×16KB boot, 2×8KB parameter, 1×32KB, 15×64KB main blocks), all independently erasable. With 70ns access time, the device supports fast code execution directly from Flash (execute-in-place) for both 8-bit and 16-bit processor systems. Operating from a single 2.7V to 3.6V supply for read, program, and erase operations, it simplifies system power design. Advanced features include Write to Buffer for fast multi-word programming, Program Suspend/Resume, Erase Suspend/Resume, and comprehensive status register for operation monitoring. Hardware block protection safeguards critical boot code and configuration data. The 32-pin plastic DIP package provides a robust through-hole form factor suitable for industrial applications. Fully specified for -40°C to +85°C industrial operation with 100,000 program/erase cycles and 10-year data retention, the M29W800DB-70N1 is ideal for 16/32-bit microprocessor systems, DSP-based equipment, industrial controllers, telecom systems, and automotive electronics.

The M29W800DB is a dual-organization NOR Flash memory that can operate in either 8-bit (byte-wide) or 16-bit (word-wide) mode, selected by the state of the BYTE# pin. In x16 mode (BYTE# = VIH), all 15 data lines (DQ0-DQ14) carry data bits, and DQ15/A-1 serves as DQ15 (the most significant data bit). In x8 mode (BYTE# = VIL), only data lines DQ0-DQ7 are used for byte data, and DQ15/A-1 becomes the A-1 address input, which selects between the high and low byte of each 16-bit word location. This allows the same 8Mbit memory array to be accessed as either 524,288 words of 16 bits or 1,048,576 bytes of 8 bits. The bottom boot architecture means the first blocks (at lowest addresses) contain the boot code. After reset, the processor starts fetching instructions from the lowest address, which is within the boot block. This block is typically hardware-protected to prevent accidental erasure. The NOR Flash array provides random access reads — any location can be read by applying its address, with data available after 70ns. Program and erase operations are command-driven, using JEDEC-standard command sequences. Write to Buffer allows loading up to 32 words (in x16 mode) or 32 bytes (in x8 mode) into an internal buffer before initiating the program operation, dramatically increasing programming throughput compared to individual word/byte programming. Program/Erase Suspend allows temporarily halting an operation to read data from another block, which is useful for systems that need to service interrupts or read calibration data during firmware update operations. The status register provides Data Polling (DQ7), Toggle Bit (DQ6), and Error Flag (DQ5) to monitor operation progress and detect failures.

• 16/32-bit microprocessor boot and firmware
• DSP program memory and data tables
• Industrial CNC and PLC controllers
• Telecom base station and line cards
• Automotive powertrain and body ECUs
• Digital set-top box code storage
• Medical imaging and diagnostics
• Defense and aerospace electronics