UT7156

The UT7156 has the following features including asynchronous operation for compatibility with industry-standard 32K×8 SRAM;CMOS and TTL compatible input and output levels;Three-state bidirectional data bus;Low operating and standby current;Latchup immune.

The UT7156 SRAM is a high performance, asynchronous,radiation-hardened, 32K x 8 random access memory conforming to industry-standard fit, form, and function.The UT7156 SRAM features fully static operation requiring no external clocks or timing strobes. UTMC designed and implemented the UT7156 SRAM using an advanced radiation-hardened (EPI-CMOS) process and a device enable/disable function resulting in a high performance, power-saving SRAM. The combination of radiation-hardness, fast access time, and low power consumption make UT7156 ideal for high-speed systems designed for operation in radiation environments.Read Cyle 1, the Address Access read in figure 3a, is initiated by a change in address inputs while the chip is enabled with G asserted and W deasserted. Valid data appears on data outputs DQ(7:0) after the specified tAVQV is satisfied. Outputs remain active throughout the entire cycle. As long as device enable and output enable are active, the address inputs may change at a rate equal to the minimum read cycle time (tAVAV).

The UT7156 SRAM incorporates special design and layout features which allow operation in high-level radiation environments. UT7156 has developed special low-temperature processing techniques designed to enhance the total-dose radiation hardness of both the gate oxide and the field oxide while maintaining the circuit density and reliability. For transient radiation hardness and latchup immunity, UT7156 builds all radiation-hardened products on epitaxial wafers using an advanced twin-tub CMOS process. In addition, UTMC pays special attention to power and ground distribution during the design phase, minimizing dose-rate upset caused by rail collapse.Stresses outside the listed absolute maximum ratings may cause permanent damage to the device.This is a stress rating only, and functional operation of the device at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended. Exposure to absolute maximum rating conamons for extended periods may affect device reliability.