參數(shù)資料
型號(hào): DS1647P-120+
廠商: Maxim Integrated Products
文件頁(yè)數(shù): 6/12頁(yè)
文件大?。?/td> 0K
描述: IC RAM TIMEKEEP NV 120NS 34-PCM
產(chǎn)品培訓(xùn)模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標(biāo)準(zhǔn)包裝: 40
類型: 時(shí)鐘/日歷
特點(diǎn): 閏年,NVSRAM
存儲(chǔ)容量: 512KB
時(shí)間格式: HH:MM:SS(24 小時(shí))
數(shù)據(jù)格式: YY-MM-DD-dd
接口: 并聯(lián)
電源電壓: 4.5 V ~ 5.5 V
電壓 - 電源,電池: 3V
工作溫度: 0°C ~ 70°C
安裝類型: 表面貼裝
封裝/外殼: 34-PowerCap? 模塊
供應(yīng)商設(shè)備封裝: 34-PowerCap 模塊
包裝: 管件
產(chǎn)品目錄頁(yè)面: 1434 (CN2011-ZH PDF)
DS1647/DS1647P
3 of 12
DESCRIPTION
The DS1647 is a 512k x 8 nonvolatile static RAM with a full-function real-time clock, which are both
accessible in a byte-wide format. The nonvolatile timekeeping RAM is functionally equivalent to any
JEDEC standard 512k x 8 SRAM. The device can also be easily substituted for ROM, EPROM and
EEPROM, providing read/write nonvolatility and the addition of the real-time clock function. The real-
time clock information resides in the eight uppermost RAM locations. The RTC registers contain year,
month, date, day, hours, minutes, and seconds data in 24-hour 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 DS1647
also contains its own power-fail circuitry, which deselects the device when the VCC supply is in an out-of-
tolerance condition. This feature prevents loss of data from unpredictable system operation brought on by
low VCC as errant access and update cycles are avoided.
PACKAGES
The DS1647 is available in two packages: 32-pin DIP and 34-pin PowerCap module. The 32-pin DIP
style module integrates the crystal, lithium energy source, and silicon all in one package. The 34-pin
PowerCap Module Board is designed with contacts for connection to a separate PowerCap (DS9034PCX)
that contains the crystal and battery. This design allows the PowerCap to be mounted on top of the
DS1647P after the completion of the surface mount process. Mounting the PowerCap after the surface
mount process prevents damage to the crystal and battery due to the high temperatures required for solder
reflow. The PowerCap is keyed to prevent reverse insertion. The PowerCap Module Board and PowerCap
are ordered separately and shipped in separate containers. The part number for the PowerCap is
DS9034PCX.
CLOCK OPERATIONS—READING THE CLOCK
While the double-buffered register structure reduces the chance of reading incorrect data, internal updates
to the DS1647 clock registers should be halted before clock data is read to prevent reading of data in
transition. However, halting the internal clock register updating process does not affect clock accuracy.
Updating is halted when a 1 is written into the read bit, the 7th most significant bit in the control register.
As long as 1 remains in that position, updating is halted. After a halt is issued, the registers reflect the
count, that is day, date, and time that was present at the moment the halt command was issued. However,
the internal clock registers of the double-buffered system continue to update so that clock accuracy is not
affected by the access of data. All of the DS1647 registers are updated simultaneously after the clock
status is reset. Updating is within a second after the read bit is written to 0.
The read bit must be a zero for a minimum of 500s to ensure that the external registers are updated.
相關(guān)PDF資料
PDF描述
VI-J0Y-MZ CONVERTER MOD DC/DC 3.3V 16.5W
VI-J0X-MZ CONVERTER MOD DC/DC 5.2V 25W
VI-J0R-MZ CONVERTER MOD DC/DC 7.5V 25W
VI-J0P-MZ CONVERTER MOD DC/DC 13.8V 25W
M83723/75A18146 CONN PLUG 14POS STRAIGHT W/SCKT
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS1647P-120+ 功能描述:實(shí)時(shí)時(shí)鐘 NV Timekeeping RAM RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 總線接口:I2C 日期格式:DW:DM:M:Y 時(shí)間格式:HH:MM:SS RTC 存儲(chǔ)容量:64 B 電源電壓-最大:5.5 V 電源電壓-最小:1.8 V 最大工作溫度:+ 85 C 最小工作溫度: 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP-8 封裝:Tube
DS1648 制造商:NSC 制造商全稱:National Semiconductor 功能描述:TRI-STATE TTL to MOS Multiplexers/Drivers
DS1648J 制造商:未知廠家 制造商全稱:未知廠家 功能描述:2-Input Digital Multiplexer
DS1648J/A+ 制造商:未知廠家 制造商全稱:未知廠家 功能描述:2-Input Digital Multiplexer
DS1649 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Hex TRI-STATEE TTL to MOS Drivers