Industrial

This application note describes the principle and application of the M41T00AUD real-time clock with audio functions. The clock can be used in printer-fax scanner units to generate beeps and audible tones.

This application note describes how to achieve high accuracy over a wide temperature range using ST's M41T82-83-93 series of RTCs, by combining the characteristics of the crystals used. This is accomplished by first measuring the frequency and then using both the analog and digital calibration features of these devices.

This application note discusses the use of clock distribution circuits in smart phone system design. As smart phones become more popular in the market, additional features such as A-GPS, Bluetooth, WLAN, and DVB-H are now included in cell phone designs. In all of these application modules, a master clock is needed, which is typically an external crystal oscillator. The master clock modulates the transmitted or received data to the proper frequency. This application note compares conventional clock trees that use discrete crystals for different modules or discrete buffer solutions to the clock solution using the integrated STCD1020/1030/1040 series circuits from STMicroelectronics (referred to as STCD10x0 throughout this application note, please refer to the STCD1020, STCD1030, STCD1040 datasheet). The benefits of using STCD10x0 are illustrated, and technical hints are given to help cell phone system designers use the STCD10x0 clock distribution solution.

This application note describes some of the most common issues related to ST's family of serial real-time clocks (RTCs), including crystal layout, oscillator circuit, undershoot protection, etc.

This application note describes how to implement a periodic alarm using ST's TIMEKEEPER M48T59 and M48T59Y. The alarm can be set for a given time and day, or to repeat at a certain day in every month, or at a certain hour in every day, or at a certain minute of every hour, or at a certain second of every minute.

This document describes the STMicroelectronics line of non-volatile SRAMs (NVRAMs) known as ZEROPOWER® or TIMEKEEPER® NVRAMs, supervisors, and serial RTCs which offer the best of both worlds: memory devices that are non-volatile like EEPROM, yet have the fast access of SRAM. The document also describes how the NVRAM works and how to predict its battery life.

By integrating a battery and power switching circuitry in its ZEROPOWER memory devices, STMicroelectronics was the first to develop non-volatile CMOS Static RAM technology. This is conventional, high speed, low power, random access, read/write memory that retains its data even when the external power is removed. By further integrating a crystal oscillator and a real time clock in the package for its TIMEKEEPER products, STMicroelectronics provides, in a single chip package, non-volatile SRAM and timekeeping that continues to run without external power. STMicroelectronics has subsequently extended the technique to work with surface mount packaging, in a product range that is known as the SNAPHAT.

Describes the digital calibration feature in TIMEKEEPER® products, this feature provides a simple and effective method to compensate for the temperature sensitivity of quartz crystals, improving system accuracy

This application note describes a problem that can occur with battery-powered NVRAM devices: negative undershoot can cause data corruption. This note provides advice on how to prevent this problem.

This document introduces the TIMEKEEPER family of products and provides detailed information on the M48T59, M48T58 and M48T559 devices.

This document describes the features and characteristics of STMicroelectronics' ZEROPOWER® and TIMEKEEPER® supervisor products. These products use surface-mount technology and are suitable for automatic assembly-line processes. They interface directly with commodity SRAM and use a commercially available cell for the internal battery, which is easily replaceable. These devices are designed for lower system costs compared to designs using competitors' hybrid products. Moreover, even though the ST products need an external SRAM chip, the footprint of the two chips together is still 80% of that of the competitors' single chip solutions.

This document describes the M40Z300W product from STMicroelectronics, Inc., which can be used to turn SRAM devices into non-volatile RAM (NVRAM). When the supply voltage falls below the preset threshold level, the device write protects the RAM, switches to its internal battery supply, and asserts the reset line. The document also explains the configuration of using two 128K x 8 SRAMs to form a 128K x 16 arrangement.

This document describes how the non-volatile static memory array and the quartz-controlled clock oscillator in STMicroelectronics' TIMEKEEPER® devices are interconnected, and how the time data is updated.