BQ4285E  RTC IC,具有 114x8 NVSRAM 和 NVSRAM 控制、针对 L 版本发出警报唤醒 3V 操作
              BQ4285E 描述
       The CMOS bq4285E/L is a low-power microprocessor peripheral providing a time-of-day clock and 100-year calendar with alarm features and battery operation. Other features include three maskable interrupt sources, square wave output, and 114 bytes of general nonvolatile storage.
A 32.768kHz output is available for sustaining power-management activities. Wake-up capability is provided by an alarm interrupt, which is active in battery-backup mode.
The bq4285E/L write-protects the clock, calendar, and storage registers during power failure. A backup battery then maintains data and operates the clock and calendar.
The bq4285E/L is a fully compatible real-time clock for IBM AT-compatible computers and other applications.
       
                
            | 
           BQ4285E | 
         
         
           | Supply Voltage(V) | 
           5   | 
         
         
           | Bus Interface | 
           Multiplexed   | 
         
         
           | Memory Density(Kb) | 
           0.114   | 
         
         
           | Operating Temperature Range(°C) | 
           0 to 70   | 
         
         
           | Pin/Package | 
           24PDIP   | 
         
         
           | Approx. Price (US$) | 
           2.90 | 1ku   | 
         
         
           | RTC Bytes | 
           14 | 
         
       
       BQ4285E 特性
       
         - Direct clock/calendar replacement for IBM(R) AT-compatible computers and other   applications   
         
 - 114 bytes of general nonvolatile storage   
         
 - Enhanced features include:
           
               - System wake-up capability—alarm interrupt output active in battery-backup   mode   
               
 - 2.7–3.6V operation (bq4285L);
                 4.5–5.5V operation (bq4285E)   
                - 2kHz output for power management
 
           
          - Automatic backup and write-protect control to external SRAM   
         
 - Functionally compatible with the DS1285   
         
 - Less than 0.5uA load under battery operation   
         
 - 14 bytes for clock/calendar and control   
         
 - BCD or binary format for clock and calendar data   
         
 - Calendar in day of the week, day of the month, months, and years, with   automatic leap-year adjustment   
         
 - Time of day in seconds, minutes, and hours
           
               - 12- or 24-hour format   
               
 - Optional daylight saving adjustment
 
           
          - Programmable square wave out-put   
         
 - Three individually maskable interrupt event flags:
           
               - Periodic rates from 122us to 500ms   
               
 - Time-of-day alarm once per second to once per day   
               
 - End-of-clock update cycle
 
           
          
       
       BQ4285E 芯片订购指南
              
                
                  | 器件 | 
                  状态 | 
                  温度 (oC) | 
                  价格(美元) | 
                  封装 | 引脚 | 
                  封装数量 | 封装载体 | 
                  丝印标记 | 
                
                
                  | BQ4285EP | 
                  ACTIVE | 
                  0 to 70 | 
                  2.90 | 1ku | 
                  PDIP (N) | 24 | 
                  15 | TUBE | 
                  4285P 
                  -SB2 | 
                
              
              BQ4285E 质量与无铅数据
              
                
                  | 器件 | 
                  环保计划* | 
                  铅/焊球涂层 | 
                  MSL 等级/回流焊峰 | 
                  环保信息与无铅 (Pb-free) | 
                  DPPM / MTBF / FIT 率 | 
                
                
                  | BQ4285EP | 
                  Pb-Free (RoHS)  | 
                  A42 SN  | 
                  N/A for Pkg Type | 
                  BQ4285EP | 
                  BQ4285EP | 
                
              
              BQ4285E 应用技术支持与电子电路设计开发资源下载
              
                - BQ4285E 数据资料   dataSheet 下载.PDF 
 
                - TI 德州仪器实时时钟产品选型与价格 . xls 
 
                - PowerPADTM Thermally   Enhanced Package
                  
                   
                  (PDF    1040 KB)                
 
                - 全面认识开关型电源中的BUCK-BOOST功率级   (Rev. A)
                  
                   
                (PDF    2206 KB)
 
                - Shelf-Life Evaluation of Lead-Free Component Finishes  (PDF  1305 KB)
 
                - PowerPADTM Made Easy  (PDF  57 KB) 
 
                - 标准线性产品交叉参考 (Rev. D)
                  
                  
                   
                (PDF    1058 KB) 
 
                - 模数规格和性能特性术语表 (Rev. A) (PDF 1993 KB) 
                
 - 所选封装材料的热学和电学性质 (PDF 645 KB) 
                
 - 高速数据转换 (PDF 1967 KB) 
 
              BQ4285E 相关工具 
              
                
                  | 名称 | 
                  型号 | 
                  公司 | 
                  工具/软件类型 | 
                
                
                  | BQ4285E 评估模块 | 
                  BQ4285EEVM | 
                  Texas Instruments | 
                  开发电路板/EVM |