WCMB4016R4X

The WCMB4016R4X is a high-performance CMOS static RAM organized as 256K words by 16 bits. This device features advanced circuit design to provide ultra-low active current. This device is ideal for portable applications such as cellular telephones. The WCMB4016R4X also has an automatic power-down feature that significantly reduces power consumption by 99% when addresses are not toggling. The WCMB4016R4X can also be put into standby mode when deselected (CE HIGH or both BLE and BHE are HIGH). The input/output pins (I/O0 through I/O15) are placed in a high-impedance state when: deselected (CE HIGH), outputs are disabled (OE HIGH), both Byte High Enable and Byte Low Enable are disabled (BHE, BLE HIGH), or during a write operation (CE LOW and WE LOW).

Writing to the WCMB4016R4X is accomplished by taking Chip Enable (CE) and Write Enable (WE) inputs LOW. If Byte Low Enable (BLE) is LOW, then data from I/O pins (I/O₀ through I/O₇), is written into the location specified on the address pins (A0 through A17). If Byte High Enable (BHE) is LOW, then data from I/O pins (I/O₈ through I/O₁₅) is written into the location specified on the address pins (A₀ through A₁₇).

Reading from the WCMB4016R4X is accomplished by taking Chip Enable (CE) and Output Enable (OE) LOW while forcing the Write Enable (WE) HIGH. If Byte Low Enable (BLE) is LOW, then data from the memory location specified by the address pins will appear on I/O0 to I/O₇. If Byte High Enable (BHE) is LOW, then data from memory will appear on I/O₈ to I/O₁₅. See the Truth Table at the back of this data sheet for a complete description of read and write modes.

The WCMB4016R4X is available in a 48-ball FBGA package.