BQ4287 具有 114x8 NVSRAM 和 NVSRAM 控制的 RTC 模块
BQ4287 描述
The CMOS bq4287 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.
The bq4287 write-protects the clock, calendar, and storage registers during power failure. The integral backup energy source then maintains data and operates the clock and calendar.
The bq4287 uses its integral battery-backup controller and battery to make a standard CMOS SRAM nonvolatile during power-fail conditions. During power-fail, the bq4287 automatically write-protects the external SRAM and provides a VCC output sourced from its internal battery.
|
BQ3287 |
BQ3287A |
BQ3287E |
BQ3287EA |
BQ4287 |
| Supply Voltage(V) |
5 |
5 |
5 |
5 |
5 |
| Bus Interface |
Multiplexed |
Multiplexed |
Multiplexed |
Multiplexed |
Multiplexed |
| Memory Density(Kb) |
0.114 |
0.114 |
0.242 |
0.242 |
0.114 |
| Operating Temperature Range(°C) |
-20 to 70,0 to 70 |
-20 to 70,0 to 70 |
0 to 70 |
0 to 70 |
0 to 70 |
| Pin/Package |
24DIP MODULE |
24DIP MODULE |
24DIP MODULE |
24DIP MODULE |
24DIP MODULE |
| Approx. Price (US$) |
4.20 | 1ku |
4.20 | 1ku |
4.20 | 1ku |
4.20 | 1ku |
5.80 | 1ku |
| RTC Bytes |
14 |
14 |
14 |
14 |
14 |
BQ4287 特性
- Direct clock/calendar replacement for IBM\xAE AT-compatible computers and other applications
- Functionally compatible with the DS1287/DS1287A and MC146818A
- 114 bytes of general nonvolatile storage
- Automatic backup supply and write-protection to make external SRAM nonvolatile
- Integral lithium cell and crystal
- 160 ns cycle time allows fast bus operation
- Intel bus timing
- 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 output
- 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
- Better than one minute per month clock accuracy
BQ4287 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 |
| BQ4287MT-SB2 |
ACTIVE |
0 to 70 |
4.20 | 1ku |
DIP MODULE (MT) | 24 |
15 |
|
BQ4287 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 |
| BQ4287MT-SB2 |
Pb-Free (RoHS) |
Call TI |
N/A for Pkg Type |
BQ4287MT-SB2 |
BQ4287MT-SB2 |
BQ4287 应用技术支持与电子电路设计开发资源下载
- BQ4287 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
- PowerPAD™ 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)
- PowerPAD™ 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)
BQ4287 相关工具
| 名称 |
型号 |
公司 |
工具/软件类型 |
| BQ4287 评估模块 |
BQ4287EVM |
Texas Instruments |
开发电路板/EVM |
