DS1743:Y2K兼容、非易失时钟RAM

The DS1743 is a full-function, year-2000-compliant (Y2KC), real-time clock/calendar (RTC) and 8k x 8 nonvolatile static RAM. User access to all registers within the DS1743 is accomplished with a bytewide interface as shown in Figure 1 in the full data sheet. The RTC information and control bits reside in the eight uppermost RAM locations. The RTC registers contain century, year, month, date, day, hours, minutes, and seconds data in 24-hour binary-coded decimal (BCD) format. Corrections for the day of the month and leap year are made automatically. The RTC clock registers are double buffered to avoid access of incorrect data that can occur during clock update cycles. The double-buffered system also prevents time loss as the timekeeping countdown continues unabated by access to time register data. The DS1743 also contains its own power-fail circuitry, which deselects the device when the VCC supply is in an out-of-tolerance condition. When VCC is above VPF, the device is fully accessible. When VCC is below VPF, the internal active-low CE signal is forced high, preventing any access. When VCC rises above VPF, access remains inhibited for TREC, allowing time for the system to stabilize. These features prevent loss of data from unpredictable system operation brought on by low VCC as errant access and update cycles are avoided.

关键特性
  • Integrated NV SRAM, Real-Time Clock, Crystal, Power-Fail Control Circuit, and Lithium Energy Source
  • Clock Registers are Accessed Identically to the Static RAM. These Registers Reside in the Eight Top RAM Locations.
  • Century Byte Register
  • Totally Nonvolatile with Over 10 Years of Operation in the Absence of Power
  • BCD-Coded Century, Year, Month, Date, Day, Hours, Minutes, and Seconds with Automatic Leap Year Compensation Valid through 2099
  • Low-Battery-Voltage Level Indicator Flag
  • Power-Fail Write Protection Allows for ±10% VCC Power-Supply Tolerance
  • Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time
  • DIP Module Only
    • Standard JEDEC Bytewide 8k x 8 Static RAM Pinout
  • PowerCap Module Board Only
    • Surface-Mountable Package for Direct Connection to PowerCap Containing Battery and Crystal
    • Replaceable Battery (PowerCap)
    • Power-On Reset Output
    • Pin-for-Pin Compatible with Other Densities of DS174XP Timekeeping RAM
功能框图
DS1743、DS1743P:原理框图
关键参数
Part NumberInterfaceVSUPPLY
(V)
Memory TypeMemory Size
(Bytes)
Time of Day AlarmsPackage/PinsBudgetary
Price
See Notes
DS1743Bytewide
3.3
5
NV SRAM8K0
EDIP/28
PCAP/34
$11.75 @1k
数据手册DataSheet
英文DS1743-DS1743P.pdfRev 5; 09/2013
技术资料
质量和环境数据
订购型号
型号状况推荐替代产品封装温度RoHS/无铅
DS1743-100停止供货DS1743-100+EDIP,;28引脚;629.9mm²0°C至+70°C参考数据资料
DS1743-100 IND停止供货DS1743-100IND+EDIP,;28引脚;629.9mm²-40°C至+85°C参考数据资料
DS1743-100+生产中EDIP,;28引脚;629.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743-100IND+生产中EDIP,;28引脚;629.9mm²-40°C至+85°CRoHS/无铅:无铅
DS1743-85+生产中EDIP,;28引脚;629.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743-85IND+生产中EDIP,;28引脚;629.9mm²-40°C至+85°CRoHS/无铅:无铅
DS1743P-100停止供货DS1743P-100+PCAP,;34引脚;596.9mm²0°C至+70°C参考数据资料
DS1743P-100+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743P-100IND停止供货DS1743P-100IND+PCAP,;34引脚;596.9mm²0°C至+70°C参考数据资料
DS1743P-100IND+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
型号状况推荐替代产品封装:类型 引脚 占位面积封装图 编码/变更 *温度RoHS/无铅?
DS1743P-85+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743P-85IND+停止供货PCAP,;34引脚;596.9mm²-40°C至+85°CRoHS/无铅:无铅
DS1743P-C01+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743W-120停止供货DS1743W-120+EDIP,;28引脚;629.9mm²0°C至+70°C参考数据资料
DS1743W-120 IND停止供货DS1743W-120IND+EDIP,;28引脚;629.9mm²-40°C至+85°C参考数据资料
DS1743W-120+生产中EDIP,;28引脚;629.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743W-120IND+生产中EDIP,;28引脚;629.9mm²-40°C至+85°CRoHS/无铅:无铅
DS1743W-150停止供货DS1743W-150+EDIP,;28引脚;629.9mm²0°C至+70°C参考数据资料
DS1743W-150+生产中EDIP,;28引脚;629.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743WP-120停止供货DS1743WP-120+PCAP,;34引脚;596.9mm²0°C至+70°C参考数据资料
型号状况推荐替代产品封装:类型 引脚 占位面积封装图 编码/变更 *温度RoHS/无铅?
DS1743WP-120+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743WP-120IND停止供货DS1743WP-120IND+PCAP,;34引脚;596.9mm²-40°C至+85°C参考数据资料
DS1743WP-120IND+生产中PCAP,;34引脚;596.9mm²-40°C至+85°CRoHS/无铅:无铅
DS1743WP-150停止供货DS1743WP-150+PCAP,;34引脚;596.9mm²0°C至+70°C参考数据资料
DS1743WP-150+生产中PCAP,;34引脚;596.9mm²0°C至+70°CRoHS/无铅:无铅
DS1743-DS1743P.pdf DS1743P
DS1743-DS1743P.pdf DS1743P
DS1743-DS1743P.pdf DS1743P
Tips for Writing Bulletproof Real-Time Clock Control Code DS3234
State Machine Logic in Binary-Coded Decimal (BCD)-Formatted Real-Time Clocks DS3234
Using a Nonvolatile Timekeeping RAM with a Microcontroller DS1747
PowerCap Package Allows for Density Upgrades, Surface Mount Assembly DS9034PCX
Design Considerations for Maxim Real-Time Clocks DS3234
DS1743P.pdf DS1743P
DS1743.pdf DS1743P