參數(shù)資料
型號: DS1643-100
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: Timer or RTC
英文描述: 1 TIMER(S), REAL TIME CLOCK, DMA28
封裝: EDIP MODULE-28
文件頁數(shù): 14/17頁
文件大小: 219K
代理商: DS1643-100
DS1643/DS1643P
6 of 17
DATA RETENTION MODE
When VCC is within nominal limits (VCC > 4.5V) the DS1643 can be accessed as described above with
read or write cycles. However, when VCC is below the power-fail point VPF (point at which write
protection occurs) the internal clock registers and RAM are blocked from access. This is accomplished
internally by inhibiting access via the CE signal. At this time the power-on reset output signal ( RST ) will
be driven active low and will remain active until VCC returns to nominal levels. When VCC falls below the
level of the internal battery supply, power input is switched from the VCC pin to the internal battery and
clock activity, RAM, and clock data are maintained from the battery until VCC is returned to nominal
level. The RST signal is an open drain output and requires a pull up. Except for the RST , all control, data,
and address signals must be powered down when VCC is powered down.
BATTERY LONGEVITY
The DS1643 has a lithium power source that is designed to provide energy for clock activity, and clock
and RAM data retention when the VCC supply is not present. The capability of this internal power supply
is sufficient to power the DS1643 continuously for the life of the equipment in which it is installed. For
specification purposes, the life expectancy is 10 years at 25
C with the internal clock oscillator running in
the absence of VCC power. Each DS1643 is shipped from Dallas Semiconductor with its lithium energy
source disconnected, guaranteeing full energy capacity. When VCC is first applied at a level greater than
VPF, the lithium energy source is enabled for battery backup operation. Actual life expectancy of the
Ds1643 will be much longer than 10 years since no lithium battery energy is consumed when VCC is
present.
相關(guān)PDF資料
PDF描述
DS1643P-100 0 TIMER(S), REAL TIME CLOCK, DMA34
DS1643P-70 0 TIMER(S), REAL TIME CLOCK, DMA34
DS1643-70 0 TIMER(S), REAL TIME CLOCK, DMA28
DS1644-120 0 TIMER(S), REAL TIME CLOCK, DMA28
DS1644P-120 0 TIMER(S), REAL TIME CLOCK, DMA34
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS1643-100+ 功能描述:實(shí)時時鐘 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 時間格式:HH:MM:SS RTC 存儲容量: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
DS1643-12 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Real-Time Clock
DS1643-120 制造商:DALLAS 制造商全稱:Dallas Semiconductor 功能描述:Nonvolatile Timekeeping RAM
DS1643-15 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Real-Time Clock
DS1643-150 制造商:DALLAS 制造商全稱:Dallas Semiconductor 功能描述:Nonvolatile Timekeeping RAM