收藏本站
DS1554 256k, Nonvolatile, Y2K-Compliant Timekeeping RAM
9 of 18
Table 3. Alarm Mask Bits
AM4
AM3
AM2
AM1
ALARM RATE
1
Once per second
1
0
When seconds match
1
0
When minutes and seconds match
1
0
When hours, minutes, and seconds match
0
When date, hours, minutes, and seconds match
When the RTC Register values match Alarm Register settings, the Alarm Flag bit (AF) is set to a 1. If
Alarm Flag Enable (AE) is also set to a 1, the alarm condition activates the
IRQ/FT pin. The IRQ/FT
signal is cleared by a read or write to the Flags Register (Address 7FF0h) as shown in Figure 2 and 3.
When
CE is active, the IRQ/FT signal may be cleared by having the address stable for as short as 15 ns
and either
OE or WE active, but is not guaranteed to be cleared unless t
RC is fulfilled. The alarm flag is
also cleared by a read or write to the Flags Register but the flag will not change states until the end of the
read/write cycle and the
IRQ/FT signal has been cleared.
Figure 2. Clearing
IRQ Waveforms
Figure 3. Clearing
IRQ Waveforms
The
IRQ/FT pin can also be activated in the battery-backed mode. The IRQ/FT will go low if an alarm
occurs and both ABE and AE are set. The ABE and AE bits are cleared during the power-up transition,
however an alarm generated during power-up will set AF. Therefore, the AF bit can be read after system
power-up to determine if an alarm was generated during the power-up sequence. Figure 4 illustrates alarm
timing during the battery-backup mode and power-up states.
0V
CE,
CE=0
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
DS1556WP-120IND IC RTC RAM Y2K 3.3V 120NS 34PCM
DS1557P-70IND IC RTC RAM Y2K 5V 70NS 34PCM
DS1558Y-TRL IC RTC W/NV RAM 5V 48-TQFP
DS1602+ IC COUNTER ELAPSED TIME 5V 8-DIP
DS1603+ IC COUNTER ELAPSED TIME 5V 7-SIP
DS1642-70+ IC RAM TIMEKEEP NV 70NS 24-EDIP
DS1643P-70+ IC RAM TIMEKEEP NV 70NS 34-PCM
DS1644P-120 IC RAM TIMEKEEP NV 120NS 34-PCM
相关代理商/技术参数
DS1554W-120IND+ 功能描述:实时时钟 256kB NV RAM Timekeeper RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS1554W-150 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:256K NV Y2KC Timekeeping RAM
DS1554WP 制造商:未知厂家 制造商全称:未知厂家 功能描述:Real-Time Clock
DS1554WP-120 功能描述:实时时钟 256kB NV RAM Timekeeper RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS1554WP-120+ 功能描述:实时时钟 256kB NV RAM Timekeeper RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS1554WP-120IND 功能描述:实时时钟 RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS1554WP-120IND+ 功能描述:实时时钟 256kB NV RAM Timekeeper RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS1554WP-150 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:256K NV Y2KC Timekeeping RAM