The CY7C1049BL-25VC is a 4Mbit asynchronous SRAM from Infineon, organized as 512K x 8 bits with a 25 ns access time. This part is a volatile memory — data is retained only while power is applied, so it suits cache, buffer, or scratchpad roles in embedded systems where the bus timing can tolerate a 25 ns window. The 25 ns access time means the memory can complete a read or write cycle in 25 ns minimum, which sets the bus cycle time for the host controller. In practice, this limits the maximum bus frequency to roughly 40 MHz if the controller can meet the setup and hold times. For designs already running at 20-33 MHz, this part fits without timing margin issues.
This means the manufacturer no longer produces the part, and no future orders can be placed through the factory. Because the part is obsolete, buyers should verify the date code and condition of any sourced units. The 36-SOJ package is a surface-mount form factor (36-BSOJ, 0.400" body width), so reflow compatibility and moisture sensitivity level (MSL) should be confirmed with the supplier before committing to a reel or tube quantity.
Package and temperature grade — design constraints
The supplier device package is 36-SOJ (Small Outline J-lead), a surface-mount package with J-bend leads on 1.27 mm pitch. The 0.400-inch (10.16 mm) body width is standard for this density. This simplifies the controller timing design because the same cycle time applies to both read and write operations.