參數(shù)資料
型號: ISL12027IBAZ-T
廠商: Intersil
文件頁數(shù): 16/28頁
文件大小: 0K
描述: IC RTC/CALENDAR EEPROM 8-SOIC
產(chǎn)品培訓(xùn)模塊: Solutions for Industrial Control Applications
標(biāo)準包裝: 2,500
類型: 時鐘/日歷
特點: 警報器,閏年,監(jiān)控器,監(jiān)視計時器
時間格式: HH:MM:SS(12/24 小時)
數(shù)據(jù)格式: YY-MM-DD-dd
接口: I²C,2 線串口
電源電壓: 2.7 V ~ 5.5 V
電壓 - 電源,電池: 1.8 V ~ 5.5 V
工作溫度: -40°C ~ 85°C
安裝類型: 表面貼裝
封裝/外殼: 8-SOIC(0.154",3.90mm 寬)
供應(yīng)商設(shè)備封裝: 8-SOIC
包裝: 帶卷 (TR)
23
FN8232.8
August 12, 2010
circuit and produce double clocking or mis-clocking, seriously
affecting the accuracy of the RTC. Care needs to be taken in
layout of the RTC circuit to avoid noise pickup. Figure 27 shows
a suggested layout for the ISL12027 or ISL12026 devices.
The X1 and X2 connections to the crystal are to be kept as
short as possible. A thick ground trace around the crystal is
advised to minimize noise intrusion, but ground near the X1
and X2 pins should be avoided as it will add to the load
capacitance at those pins. Keep in mind these guidelines for
other PCB layers in the vicinity of the RTC device. A small
decoupling capacitor at the VDD pin of the chip is mandatory,
with a solid connection to ground (see Figure 27).
Oscillator Measurements
When a proper crystal is selected and the layout guidelines
above are observed, the oscillator should start up in most
circuits in less than one second. Some circuits may take slightly
longer, but start-up should definitely occur in less than 5s.
When testing RTC circuits, the most common impulse is to
apply a scope probe to the circuit at the X2 pin (oscillator
output) and observe the waveform. DO NOT DO THIS!
Although in some cases you may see a usable waveform, due
to the parasitics (usually 10pF to ground) applied with the
scope probe, there will be no useful information in that
waveform other than the fact that the circuit is oscillating. The
X2 output is sensitive to capacitive impedance so the voltage
levels and the frequency will be affected by the parasitic
elements in the scope probe. Applying a scope probe can
possibly cause a faulty oscillator to start-up, hiding other issues
(although in the Intersil RTC’s, the internal circuitry assures
startup when using the proper crystal and layout).
The best way to analyze the RTC circuit is to power it up and
read the real time clock as time advances. Alternatively the
frequency can be checked by setting an alarm for each minute.
Using the pulse interrupt mode setting, the once-per-minute
interrupt functions as an indication of proper oscillation.
Backup Battery Operation
Many types of batteries can be used with the Intersil RTC
products. 3.0V or 3.6V Lithium batteries are appropriate, and
sizes are available that can power a Intersil RTC device for
up to 10 years. Another option is to use a supercapacitor for
applications where VDD may disappear intermittently for
short periods of time. Depending on the value of
TABLE 8. CRYSTAL PARAMETERS REQUIRED FOR INTERSIL RTC’S
PARAMETER
MIN
TYP
MAX
UNITS
NOTES
Frequency
32.768
kHz
Frequency Tolerance
±100
ppm
Down to 20ppm if desired
Turnover Temperature
20
25
30
°C
Typically the value used for most crystals
Operating Temperature Range
-40
85
°C
Parallel Load Capacitance
12.5
pF
Equivalent Series Resistance
50
k
Ω
For best oscillator performance
TABLE 9. CRYSTAL MANUFACTURERS
MANUFACTURER
PART NUMBER
TEMP RANGE (°C)
+25°C FREQUENCY TOLERANCE (ppm)
Citizen
CM201, CM202, CM200S
-40 to +85
±20
Epson
MC-405, MC-406
-40 to +85
±20
Raltron
RSM-200S-A or B
-40 to +85
±20
SaRonix
32S12A or B
-40 to +85
±20
Ecliptek
ECPSM29T-32.768K
-10 to +60
±20
ECS
ECX-306/ECX-306I
-10 to +60
±20
Fox
FSM-327
-40 to +85
±20
FIGURE 27. SUGGESTED LAYOUT FOR INTERSIL RTC IN SO-8
C1
01F
U1
ISL12027
XTAL1
32.768kHZ
10k
R1
ISL12027, ISL12027A
相關(guān)PDF資料
PDF描述
VI-JVM-MZ CONVERTER MOD DC/DC 10V 25W
ISL12027IB30AZ-T IC RTC/CALENDAR EEPROM 8-SOIC
ISL12027IBZ-T IC RTC/CALENDAR EEPROM 8-SOIC
VI-JVK-MZ CONVERTER MOD DC/DC 40V 25W
ISL1218IBZ IC RTC LP BATT BACKED SRAM 8SOIC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL12027IBZ 功能描述:實時時鐘 REAL TIME CLK/CLNDR W/EEPROM IN 8LD 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
ISL12027IBZ-T 功能描述:實時時鐘 REAL TIME CLK/CLNDR W/EEPROM IN 8LD 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
ISL12027IV27AZ 功能描述:實時時鐘 REAL TIME CLK/CLNDR W/EEPROM 2 92VSET 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
ISL12027IV27AZ-T 功能描述:實時時鐘 REAL TIME CLK/CLNDR W/EEPROM 2 92VSET 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
ISL12027IV27Z 功能描述:實時時鐘 REAL TIME CLK/CLNDR W/EEPROM 2 7VSET 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