## Overview of STK17TA8-RF45 The **STK17TA8-RF45** is a high-performance **1Mb (128K x 8) nvSRAM** (Non-volatile Static Random Access Memory) with an integrated **Real-Time Clock (RTC)**. It is manufactured by Cypress Semiconductor (now part of Infineon Technologies). This component combines the speed of an SRAM with the non-volatile storage capabilities of an EEPROM, making it ideal for systems that require frequent data updates and data retention during power loss. --- ### Technical Specifications | Parameter | Specification | |:---|:---| | **Memory Capacity** | 1 Mbit (128K x 8 bits) | | **Speed/Access Time** | 45 ns | | **Interface** | Parallel | | **Operating Voltage** | 2.7V to 3.6V | | **Package Type** | 48-pin SSOP (Small Shrink Outline Package) | | **Operating Temperature** | Commercial (0°C to 70°C) or Industrial (-40°C to 85°C) | | **Data Retention** | 20 Years (Minimum) | --- ### Core Electronic Components & Architecture 1. **SRAM Cell:** Used for primary high-speed read/write operations. It behaves like a standard fast SRAM with a 45ns access time. 2. **Non-volatile Element (QuantumTrap):** Each SRAM cell is paired with a non-volatile element. When power fails, the data is automatically transferred from the SRAM to this non-volatile storage. 3. **Real-Time Clock (RTC):** An internal clock providing time-of-day (seconds, minutes, hours) and calendar (day, date, month, year) information. It includes leap year compensation. 4. **Internal Capacitor Control:** The device typically utilizes a "STORE" operation triggered by a power-down event (AutoStore). It monitors $V_{CC}$ and uses a small external capacitor to provide enough energy to move data into non-volatile memory. --- ### Key Features * **AutoStore:** Automatically saves SRAM data to non-volatile memory upon power loss. * **Hardware RECALL:** Manually restores data from non-volatile memory back to the SRAM on power-up. * **Infinite Endurance:** Since reads/writes occur in the SRAM portion, there is no wear-out mechanism like standard Flash or EEPROM (up to $10^{14}$ cycles). * **RTC Functions:** Includes alarm features, watchdog timers, and software calibration. --- ### Pin Configuration (Common Signals) | Pin Name | Function | |:---|:---| | **A0 - A16** | Address Inputs | | **DQ0 - DQ7** | Data Input/Output | | **$\overline{CE}$** | Chip Enable | | **$\overline{WE}$** | Write Enable | | **$\overline{OE}$** | Output Enable | | **$V_{CAP}$** | Connection for external capacitor for AutoStore | | **INT** | Interrupt Output (for RTC alarms) | --- ### Applications * **Industrial Control:** Storing configuration and state data. * **Data Logging:** High-speed logging where data must survive sudden power failures. * **Medical Equipment:** Monitoring devices requiring accurate time-stamping and zero-latency storage. * **RAID Controllers:** Cache metadata storage.