参数资料
型号: DS12CR887-33+
厂商: Maxim Integrated Products
文件页数: 3/23页
文件大小: 0K
描述: IC RTC W/RAM 128 BYTE 24-EDIP
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 31
类型: 时钟/日历
特点: 警报器,闰年,NVSRAM,方波输出,涓流充电器
存储容量: 114B
时间格式: HH:MM:SS(12/24 小时)
数据格式: YY-MM-DD-dd
接口: 并联
电源电压: 2.97 V ~ 3.63 V
工作温度: -40°C ~ 85°C
安装类型: 通孔
封装/外壳: 24-DIP 模块(0.600",15.24mm)
供应商设备封装: 24-EDIP
包装: 管件
产品目录页面: 1433 (CN2011-ZH PDF)
DS12R885/DS12CR887/DS12R887
RTCs with Constant-Voltage Trickle Charger
11
Maxim Integrated
Pin Description (continued)
PIN
SO
EDIP
BGA
NAME
FUNCTION
18
A2
RESET
Reset Input. The active-low RESET pin has no effect on the clock, calendar, or RAM. On
power-up, the RESET pin can be held low for a time to allow the power supply to
stabilize. The amount of time that RESET is held low is dependent on the application.
However, if RESET is used on power-up, the time RESET is low should exceed 200ms to
ensure that the internal timer that controls the DS12R885 on power-up has timed out.
When RESET is low and VCC is above VPF, the following occurs:
A. Periodic interrupt-enable (PIE) bit is cleared to 0.
B. Alarm interrupt-enable (AIE) bit is cleared to 0.
C. Update-ended interrupt-enable (UIE) bit is cleared to 0.
D. Periodic-interrupt flag (PF) bit is cleared to 0.
E. Alarm-interrupt flag (AF) bit is cleared to 0.
F. Update-ended interrupt flag (UF) bit is cleared to 0.
G. Interrupt-request status flag (IRQF) bit is cleared to 0.
H. IRQ pin is in the high-impedance state.
I. The device is not accessible until RESET is returned high.
J. Square-wave output-enable (SQWE) bit is cleared to 0.
In a typical application, RESET can be connected to VCC. This connection allows the
DS12R885 to go in and out of power fail without affecting any of the control registers.
19
A4
IRQ
Interrupt Request Output. The IRQ pin is an active-low output of the DS12R885 that can
be used as an interrupt input to a processor. The IRQ output remains low as long as the
status bit causing the interrupt is present and the corresponding interrupt-enable bit is
set. The processor program normally reads the C register to clear the IRQ pin. The
RESET pin also clears pending interrupts. When no interrupt conditions are present, the
IRQ level is in the high-impedance state. Multiple interrupting devices can be
connected to an IRQ bus, provided that they are all open drain. The IRQ pin is an open-
drain output and requires an external pullup resistor to VCC.
20
VBACKUP
Connection for Rechargeable Battery or Super Cap. This pin provides trickle charging
when VCC is greater than VBACKUP. On the DS12CR887 and DS12R887, the VBACKUP pin
is missing and is internally connected to a lithium cell.
21
A5
RCLR
RAM Clear. The active-low RCLR pin is used to clear (set to logic 1) all 114 bytes of
general-purpose RAM, but does not affect the RAM associated with the RTC. To clear
the RAM, RCLR must be forced to an input logic 0 during battery-backup mode when
VCC is not applied. The RCLR function is designed to be used through a human
interface (shorting to ground manually or by a switch) and not to be driven with external
buffers. This pin is internally pulled up. Do not use an external pullup resistor on this
pin.
23
C4
SQW
Square-Wave Output. The SQW pin can output a signal from one of 13 taps provided by
the 15 internal divider stages of the RTC. The frequency of the SQW pin can be changed
by programming Register A, as shown in Table 3. The SQW signal can be turned on and
off using the SQWE bit in Register B. The SQW signal is not available when VCC is less
than VPF.
24
A6–A8,
B1–B8,
C6–C8
VCC
DC Power Pin for Primary Power Supply. When VCC is applied within normal limits, the
device is fully accessible and data can be written and read. When VCC is below VPF
reads and writes are inhibited.
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DS12CR887-5 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
DS12CR887-5+ 功能描述:实时时钟 RTC w/Constant V Trickle Charger 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
DS12R885-33 制造商:Maxim Integrated Products 功能描述:REAL TIME CLOCK MULTIPLEXED 114BYTE - Bulk
DS12R885-5 制造商:Maxim Integrated Products 功能描述:REAL TIME CLOCK MULTIPLEXED 114BYTE - Bulk