DS1254
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DETAILED DESCRIPTION
The DS1254 is a fully nonvolatile static RAM (NV SRAM) (organized as 2M words by 8 bits) with built-in real-time
clock. It has a self-contained lithium energy source and control circuitry that constantly monitors VCC for an out-of-
tolerance condition. When such a condition occurs, the DS1254 makes use of an attached DS3800 battery cap to
maintain clock information and preserve stored data while protecting that data by disallowing all memory accesses.
Additionally, the DS1254 has dedicated circuitry for monitoring the status of an attached DS3800 battery cap.
The phantom clock provides timekeeping information including hundredths of seconds, seconds, minutes, hours,
day, date, month, and year information. The date at the end of the month is automatically adjusted for months with
fewer than 31 days, including correction for leap years. The phantom clock operates in either 24-hour or 12-hour
format with an AM/PM indicator.
Because the DS1254 has a total of 168 balls and only 35 active signals, balls are wired together into groups, thus
providing redundant connections for every signal.
Figure 1. Pin Configuration
VCC
A7
A6
A5
GND
A4
A3
A2
A1
1
2
3
4
5
6
7
8
9
29
28
27
26
25
24
23
22
21
10
11
12
13
14
15
16
17
18
19
20
41
40
39
38
37
36
35
34
33
32
31
30
VCC
A17
A18
A19
GND
A20
CE
OE
WE
A0
DQ0
DQ1
DQ2
DQ3
GND
DQ4
DQ5
DQ6
DQ7
BW
V
CC
A8
A9
A10
A11
GND
A12
A13
A14
A15
A16
V
CC
RECEPTACLES FOR
DS3800 BATTERY CAP
PINS
GND
VBAT
Dallas Semiconductor
DS1254
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相关代理商/技术参数
DS1254WB2-150 功能描述:实时时钟 2M X 8 NV SRAM w/Phantom Clock 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
DS1254WB-C01 功能描述:实时时钟 2M X 8 NV SRAM w/Phantom Clock 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
DS1254WB-C02 功能描述:实时时钟 2M X 8 NV SRAM w/Phantom Clock 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
DS1254YB-100 功能描述:IC NVSRAM 16MBIT 100NS 168BGA RoHS:否 类别:集成电路 (IC) >> 时钟/计时 - 实时时钟 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- 类型:时钟/日历 特点:警报器,闰年,SRAM 存储容量:- 时间格式:HH:MM:SS(12/24 小时) 数据格式:YY-MM-DD-dd 接口:SPI 电源电压:2 V ~ 5.5 V 电压 - 电源,电池:- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-WDFN 裸露焊盘 供应商设备封装:8-TDFN EP 包装:管件
DS1254YB2-100 功能描述:实时时钟 2M X 8 NV SRAM w/Phantom Clock 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
DS125-6-2G 制造商:Electronic Hardware Corporation (EHC) 功能描述:CRANK HANDLE ROUND KNOB 6.35MM 制造商:EHC (ELECTRONIC HARDWARE) 功能描述:CRANK HANDLE ROUND KNOB, 6.35MM 制造商:EHC (ELECTRONIC HARDWARE) 功能描述:CRANK HANDLE ROUND KNOB, 6.35MM; Knob / Dial Style:Round with Crank Handle; Shaft Diameter:6.35mm; Knob Diameter:31.75mm; Shaft Type:Round; Knob Material:Plastic; Shaft Size:1/4 (6.35) in. (mm) ;RoHS Compliant: Yes
DS1258AB-100 功能描述:NVRAM RoHS:否 制造商:Maxim Integrated 数据总线宽度:8 bit 存储容量:1024 Kbit 组织:128 K x 8 接口类型:Parallel 访问时间:70 ns 电源电压-最大:5.5 V 电源电压-最小:4.5 V 工作电流:85 mA 最大工作温度:+ 70 C 最小工作温度:0 C 封装 / 箱体:EDIP 封装:Tube
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