The **STK14CA8-R45** is a high-performance **nvSRAM** (Non-volatile Static Random Access Memory) manufactured by Infineon Technologies (formerly Cypress Semiconductor). It integrates a standard SRAM cell with a non-volatile QuantumTrap cell in a single monolithic chip. --- ## 1. Key Specifications | Feature | Specification | | :--- | :--- | | **Memory Density** | 1 Mbit (128K x 8) | | **Access Time** | 45 ns | | **Interface** | Parallel (Standard SRAM Interface) | | **Supply Voltage** | 2.7V to 3.6V (3.3V nominal) | | **Package** | 32-pin SOIC or 48-pin SSOP | | **Data Retention** | 20 Years | | **Read/Write Cycles** | Unlimited (SRAM) | --- ## 2. Core Functional Components ### A. The nvSRAM Technology The STK14CA8 is unique because it combines two types of memory in every bit cell: 1. **SRAM Cell:** Provides fast, unlimited read/write cycles at 45ns speeds. 2. **QuantumTrap Cell:** A non-volatile element that stores the SRAM data when power is lost. ### B. AutoStore™ Feature This is the most critical electronic part of the device's logic. It monitors the $V_{CC}$ (Power Supply). If the voltage falls below a threshold, the device automatically transfers all data from the volatile SRAM to the non-volatile QuantumTrap cells. * **Capacitor Requirement:** It requires a small external capacitor ($V_{CAP}$) to provide the power necessary to complete the data transfer during a power failure. ### C. Hardware and Software Controls * **Hardware STORE/RECALL:** Pins are provided to manually trigger a data transfer between the volatile and non-volatile layers. * **Software Sequences:** Specific patterns of read/write operations can be used to initiate "Store" or "Recall" commands without using extra hardware pins. --- ## 3. Pin Configuration Overview | Pin Name | Function | Description | | :--- | :--- | :--- | | **A0 - A16** | Address Inputs | Used to select one of the 131,072 bytes. | | **DQ0 - DQ7** | Data I/O | Bidirectional data bus. | | **$\overline{CE}$** | Chip Enable | Activates the device. | | **$\overline{WE}$** | Write Enable | Enables write operations. | | **$\overline{OE}$** | Output Enable | Controls the output drivers during read. | | **$V_{CAP}$** | Capacitor Pin | Connection for the power-backup capacitor. | | **$\overline{HSB}$** | Hardware Status Busy | Signals if a Store/Recall operation is in progress. | --- ## 4. Typical Applications * **Industrial Automation:** Storing configuration and state data in case of sudden power loss. * **Data Logging:** High-speed writing where data loss is unacceptable. * **RAID Controllers:** Storing cache metadata. * **Medical Equipment:** Maintaining critical patient settings.