数据搜索系统,热门电子元器件搜索
  Chinese  ▼
ALLDATASHEETCN.COM

X  

X1227V8 数据表(PDF) 3 Page - Xicor Inc.

部件名 X1227V8
功能描述  Real Time Clock/Calendar/CPU Supervisor with EEPROM
Download  28 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
制造商  XICOR [Xicor Inc.]
网页  http://www.xicor.com
标志 XICOR - Xicor Inc.

X1227V8 数据表(HTML) 3 Page - Xicor Inc.

  X1227V8 Datasheet HTML 1Page - Xicor Inc. X1227V8 Datasheet HTML 2Page - Xicor Inc. X1227V8 Datasheet HTML 3Page - Xicor Inc. X1227V8 Datasheet HTML 4Page - Xicor Inc. X1227V8 Datasheet HTML 5Page - Xicor Inc. X1227V8 Datasheet HTML 6Page - Xicor Inc. X1227V8 Datasheet HTML 7Page - Xicor Inc. X1227V8 Datasheet HTML 8Page - Xicor Inc. X1227V8 Datasheet HTML 9Page - Xicor Inc. Next Button
Zoom Inzoom in Zoom Outzoom out
 3 / 28 page
background image
X1227
REV 1.1.20 1/13/03
Characteristics subject to change without notice.
3 of 28
www.xicor.com
POWER CONTROL OPERATION
The power control circuit accepts a VCC and a VBACK
input. The power control circuit powers the device from
VBACK when VCC < VBACK - 0.2V. It will switch back to
power the device from VCC when VCC exceeds VBACK.
Figure 2. Power Control
REAL TIME CLOCK OPERATION
The Real Time Clock (RTC) uses an external
32.768kHz quartz crystal to maintain an accurate
internal representation of the second, minute, hour,
day, date, month, and year. The RTC has leap-year
correction. The clock also corrects for months having
fewer than 31 days and has a bit that controls 24 hour
or AM/PM format. When the X1227 powers up after
the loss of both VCC and VBACK, the clock will not
operate until at least one byte is written to the clock
register.
Reading the Real Time Clock
The RTC is read by initiating a Read command and
specifying the address corresponding to the register of
the Real Time Clock. The RTC Registers can then be
read in a Sequential Read Mode. Since the clock runs
continuously and a read takes a finite amount of time,
there is the possibility that the clock could change during
the course of a read operation. In this device, the time is
latched by the read command (falling edge of the clock
on the ACK bit prior to RTC data output) into a separate
latch to avoid time changes during the read operation.
The clock continues to run. Alarms occurring during a
read are unaffected by the read operation.
Writing to the Real Time Clock
The time and date may be set by writing to the RTC
registers. To avoid changing the current time by an
uncompleted write operation, the current time value is
loaded into a separate buffer at the falling edge of the
clock on the ACK bit before the RTC data input bytes,
the clock continues to run. The new serial input data
replaces the values in the buffer. This new RTC value
is loaded back into the RTC Register by a stop bit at
the end of a valid write sequence. An invalid write
operation aborts the time update procedure and the
contents of the buffer are discarded. After a valid write
operation the RTC will reflect the newly loaded data
beginning with the next “one second” clock cycle after
the stop bit is written. The RTC continues to update
the time while an RTC register write is in progress and
the RTC continues to run during any nonvolatile write
sequences. A single byte may be written to the RTC
without affecting the other bytes.
Accuracy of the Real Time Clock
The accuracy of the Real Time Clock depends on the
frequency of the quartz crystal that is used as the time
base for the RTC. Since the resonant frequency of a
crystal is temperature dependent, the RTC perfor-
mance will also be dependent upon temperature. The
frequency deviation of the crystal is a fuction of the
turnover temperature of the crystal from the crystal’s
nominal frequency. For example, a >20ppm frequency
deviation translates into an accuracy of >1 minute per
month. These parameters are available from the
crystal manufacturer. Xicor’s RTC family provides on-
chip crystal compensation networks to adjust load-
capacitance to tune oscillator frequency from +116
ppm to –37 ppm when using a 12.5 pF load crystal.
For more detail information see the Application
section.
CLOCK/CONTROL REGISTERS (CCR)
The Control/Clock Registers are located in an area
separate from the EEPROM array and are only
accessible following a slave byte of “1101111x” and
reads or writes to addresses [0000h:003Fh]. The
clock/control memory map has memory addresses
from 0000h to 003Fh. The defined addresses are
described in the Table 1. Writing to and reading from
the undefined addresses are not recommended.
CCR access
The contents of the CCR can be modified by perform-
ing a byte or a page write operation directly to any
address in the CCR. Prior to writing to the CCR
(except the status register), however, the WEL and
RWEL bits must be set using a two step process (See
section “Writing to the Clock/Control Registers.”)
The CCR is divided into 5 sections. These are:
1. Alarm 0 (8 bytes; non-volatile)
2. Alarm 1 (8 bytes; non-volatile)
3. Control (4 bytes; non-volatile)
4. Real Time Clock (8 bytes; volatile)
5. Status (1 byte; volatile)
VBACK
In
Voltage
VCC
On
Off


类似零件编号 - X1227V8

制造商部件名数据表功能描述
logo
Intersil Corporation
X1227V8 INTERSIL-X1227V8 Datasheet
422Kb / 28P
   2-Wire RTC Real TimeClock/Calendar/CPU Supervisor with EEPROM
X1227V8 INTERSIL-X1227V8 Datasheet
405Kb / 28P
   2-Wire??RTC Real TimeClock/Calendar/ CPU Supervisor with EEPROM
logo
Renesas Technology Corp
X1227V8 RENESAS-X1227V8 Datasheet
1Mb / 28P
   2-Wire??RTC Real TimeClock/Calendar/CPU Supervisor with EEPROM
logo
Intersil Corporation
X1227V8-2.7 INTERSIL-X1227V8-2.7 Datasheet
422Kb / 28P
   2-Wire RTC Real TimeClock/Calendar/CPU Supervisor with EEPROM
X1227V8-2.7 INTERSIL-X1227V8-2.7 Datasheet
405Kb / 28P
   2-Wire??RTC Real TimeClock/Calendar/ CPU Supervisor with EEPROM
More results

类似说明 - X1227V8

制造商部件名数据表功能描述
logo
Xicor Inc.
X1228 XICOR-X1228 Datasheet
569Kb / 31P
   Real Time Clock/Calendar/CPU Supervisor with EEPROM
logo
Intersil Corporation
X1228 INTERSIL-X1228 Datasheet
430Kb / 29P
   Real Time Clock/Calendar/CPU Supervisor with EEPROM
X1228 INTERSIL-X1228_06 Datasheet
421Kb / 29P
   Real Time Clock/Calendar/CPU Supervisor with EEPROM
X1286 INTERSIL-X1286_06 Datasheet
473Kb / 25P
   Intersil Real Time Clock/Calendar/CPU Supervisor with EEPROM
X1286V14T1 INTERSIL-X1286V14T1 Datasheet
482Kb / 25P
   Intersil Real Time Clock/Calendar/CPU Supervisor with EEPROM
April 14, 2006
X1286 INTERSIL-X1286 Datasheet
365Kb / 25P
   Intersil Real Time Clock/Calendar/CPU Supervisor with EEPROM X1286
X1288 INTERSIL-X1288 Datasheet
428Kb / 27P
   2-Wire??RTC Real Time Clock/Calendar/CPU Supervisor with EEPROM
logo
Renesas Technology Corp
X1288 RENESAS-X1288 Datasheet
1Mb / 27P
   2-Wire??RTC Real Time Clock/Calendar/CPU Supervisor with EEPROM
logo
Xicor Inc.
X1288 XICOR-X1288 Datasheet
560Kb / 31P
   2-Wire RTC Real Time Clock/Calendar/CPU Supervisor with EEPROM
logo
Intersil Corporation
ISL12027 INTERSIL-ISL12027_10 Datasheet
390Kb / 28P
   Real Time Clock/Calendar with EEPROM
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28


数据表 下载

Go To PDF Page


链接网址




隐私政策
ALLDATASHEETCN.COM
ALLDATASHEET是否为您带来帮助?  [ DONATE ] 

关于 Alldatasheet   |   广告服务   |   联系我们   |   隐私政策   |   链接交换   |   制造商名单
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com