STK14C88-3NF35I

The purpose of the µF capacitor tied from VCAP to ground in the Simtek STK14C88-3 memory device is to guarantee the STORE operation, regardless of power-down slew rate or loss of power from "hot swapping" .

The STORE cycle in the Simtek STK14C88-3 memory device can be initiated by executing sequential E controlled READ cycles from six specific address locations. During the STORE cycle, an erase of the previous nonvolatile data is first performed, followed by a program of the nonvolatile elements. Once a STORE cycle is initiated, further input and output are disabled until the cycle is completed. It is important that no other READ or WRITE accesses intervene in the sequence, or the sequence will be aborted and no STORE will take place. The six consecutive addresses must be in the order listed in the Hardware Mode Selection Table: 0E38, 31C7, 03E0, 3C1F, 303F, 0FC0. W must be high during all six consecutive cycles to enable a nonvolatile cycle. The RECALL cycle in the Simtek STK14C88-3 memory device can be initiated by performing a sequence of E controlled READ operations. The RECALL cycle is a two-step procedure where the SRAM data is cleared first, and then the nonvolatile information is transferred into the SRAM cells. After the RECALL cycle time, the SRAM will be ready for READ and WRITE operations again. The nonvolatile data can be recalled an unlimited number of times. The sequence of E controlled READ operations to initiate the RECALL cycle includes reading specific addresses: 0E38, 31C7, 03E0, 3C1F, 303F, and 0C63. W must be high during all six consecutive cycles to enable the RECALL cycle.

The Simtek STK14C88-3 memory device has the following features mentioned in the document: 1. Typical ICC of 10mA at 200ns Cycle Time . 2. Unlimited READ, WRITE, and RECALL Cycles . 3. 1,000,000 STORE Cycles to nonvolatile elements (Commercial/Industrial) . 4. 100-Year Data Retention in nonvolatile elements (Commercial/Industrial) . 5. Single 3.3V + 0.3V Operation . 6. Available in Commercial and Industrial Temperatures . 7. Comes in 32-Pin SOIC and DIP Packages . 8. Has two separate modes of operation: SRAM mode and nonvolatile mode . 9. Requires a 68 µF or larger capacitor tied from VCAP to ground for the STORE operation . 10. Requires a high-frequency bypass capacitor of approximately 0.1 µF connected between VCAP and VSS for noise considerations . 11. Performs a READ cycle when E and G are low and W and HSB are high . STK14C88-3.