Functional Description
This family of secondary cache modules is designed for Intel P54C/P55C systems with the OPTi Viper chip set.
CYM74B550 is a low cost asynchronous cache module that provides 256-Kbytes of cache with industry standard 32Kx8 5 volt SRAMs and 3.3 volt level translators. These modules offer 3-2-2-2 performance at CPU bus speeds up to 66 MHz.
The synchronous modules are available with low cost synchronous pipelined RAMs or high performance synchronous burst RAMs.
The CYM74P550A is a high performance synchronous pipelined burst 256 KB module and is based on industry standard 32Kx32 pipelined BSRAM. The CYM74P550A has series damping resistors on the data lines.
The CYM74S550 and CYM74S551 are high performance synchronous burst cache modules that provide 256-Kbytes and 512-Kbytes of cache respectively. These modules support 3-1-1-1 performance at 66 MHz.
All of these modules include storage for 8-bits of tag and one dirty bit. Multiple ground pins and on-board decoupling capacitors ensure high performance with maximum noise immunity.
All components on the cache modules are surface mounted on a multi-layer epoxy laminate (FR-4) substrate. The contact pins are plated with 100 micro-inches of nickel covered by 10 micro-inches of gold flash.

FEATUREs
• Pin-compatible secondary cache module family
• Asynchronous (CYM74B550), synchronous pipelined (CYM74P550A), or synchronous burst (CYM74S550, CYM74S551) modules
• Ideal for Intel P54C/P55C systems with the OPTi Viper chipset
• Operates at 50, 60, and 66 MHz
• Uses cost-effective CMOS asynchronous SRAMs or high-performance synchronous SRAMs
• 160-position Burndy DIMM CELP2X80SC3Z48 connector
• 3.3V inputs/ data outputs