參數(shù)資料
型號: ISL12029IVAZ
廠商: Intersil
文件頁數(shù): 9/29頁
文件大?。?/td> 0K
描述: IC RTC/CALENDAR EEPROM 14-TSSOP
標(biāo)準(zhǔn)包裝: 960
類型: 時(shí)鐘/日歷
特點(diǎn): 警報(bào)器,閏年,監(jiān)控器,監(jiān)視計(jì)時(shí)器
時(shí)間格式: HH:MM:SS(12/24 小時(shí))
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: 14-TSSOP(0.173",4.40mm 寬)
供應(yīng)商設(shè)備封裝: 14-TSSOP
包裝: 管件
17
FN6206.10
December 16, 2010
OPTION 2 - LEGACY POWER CONTROL MODE
(DEFAULT FOR ISL12029)
The Legacy Mode follows conditions set in X1226 products.
In this mode, switching from VDD to VBAT is simply done by
comparing the voltages and the device operates from
whichever is the higher voltage. Care should be taken when
changing from Normal to Legacy Mode. If the VBAT voltage is
higher than VDD, then the device will enter battery backup and
unless the battery is disconnected or the voltage decreases,
the device will no longer operate from VDD. If that is the
situation on initial power-up, then I2C communication may not
be possible. For these applications, the ISL12029A should be
used.
To select the Option 2, BSW bit in the Power Register must
be set to “BSW = 1.”
Normal Mode (VDD) to Battery Backup Mode (VBAT)
To transition from the VDD to VBAT mode, the following
conditions must be met:
VDD < VBAT - VBATHYS
Battery Backup Mode (VBAT) to Normal Mode (VDD)
The device will switch from the VBAT to VDD mode when the
following condition occurs:
VDD > VBAT +VBATHYS
The Legacy Mode power control conditions are illustrated in
Figure 15.
Power-on Reset
Application of power to the ISL12029 activates a Power-on
Reset Circuit that pulls the RESET pin active. This signal
provides several benefits.
- It prevents the system microprocessor from starting to
operate with insufficient voltage.
- It prevents the processor from operating prior to
stabilization of the oscillator.
- It allows time for an FPGA to download its configuration
prior to initialization of the circuit.
- It prevents communication to the EEPROM, greatly
reducing the likelihood of data corruption on power-up.
When VDD exceeds the device VRESET threshold value for
typically 250ms the circuit releases RESET, allowing the
system to begin operation. Recommended slew rate is
between 0.2V/ms and 50V/ms.
NOTE: If the VBAT voltage drops below the data sheet
minimum of 1.8V and the VDD power cycles to 0V then back
to VDD voltage, then the RESET output may stay low and the
I2C communications will not operate. The VBAT and VDD
power will need to be cycled to 0V together to allow normal
operation again.
Watchdog Timer Operation
The Watchdog timer time-out period is selectable. By writing
a value to WD1 and WD0, the Watchdog timer can be set to
3 different time-out periods or off. When the Watchdog timer
is set to off, the Watchdog circuit is configured for low power
operation (see Table 8).
Watchdog Timer Restart
The Watchdog Timer is started by a falling edge of SDA
when the SCL line is high (START condition). The start
signal restarts the Watchdog timer counter, resetting the
period of the counter back to the maximum. If another
START fails to be detected prior to the Watchdog timer
expiration, then the RESET pin becomes active for one reset
time out period. In the event that the start signal occurs
during a reset time out period, the start will have no effect.
When using a single START to refresh Watchdog timer, a
STOP condition should be followed to reset the device back
to stand-by mode (see Figure 3).
In battery mode, the Watchdog timer function is disabled.
Low Voltage Reset (LVR) Operation
When a power failure occurs, a voltage comparator
compares the level of the VDD line versus a preset threshold
voltage (VRESET), then generates a RESET pulse if it is
below VRESET. The reset pulse will time-out 250ms after the
VDD line rises above VRESET. If the VDD remains below
VRESET, then the RESET output will remain asserted low.
Power-up and power-down waveforms are shown in
Figure 4. The LVR circuit is to be designed so the RESET
signal is valid down to VDD =1.0V.
When the LVR signal is active, unless the part has been
switched into the battery mode
, the completion of an
in-progress non-volatile write cycle is unaffected, allowing a
non-volatile write to continue as long as possible (down to
the Reset Valid Voltage). The LVR signal, when active, will
terminate any in-progress communications to the device and
prevents new commands from disrupting any current write
VBAT
IN
VOLTAGE
VDD
ON
OFF
FIGURE 15. BATTERY SWITCHOVER IN LEGACY MODE
TABLE 8. WATCHDOG TIMER OPERATION
WD1
WD0
DURATION
1
disabled
1
0
250ms
0
1
750ms
0
1.75s
ISL12029, ISL12029A
相關(guān)PDF資料
PDF描述
ISL12029IV30AZ IC RTC/CALENDAR EEPROM 14-TSSOP
VI-BN4-MW-B1 CONVERTER MOD DC/DC 48V 100W
D38999/26FH21PA CONN PLUG 21POS STRAIGHT W/PINS
VI-BN4-MV CONVERTER MOD DC/DC 48V 150W
MS27474E16F26PB CONN RCPT 26POS JAM NUT W/PINS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL12029IVAZ-T 功能描述:實(shí)時(shí)時(shí)鐘 REAL TIME CLKRTC W/ EPROM 4 64VSET 14 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(shí)間格式:HH:MM:SS RTC 存儲(chǔ)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
ISL12029IVZ 功能描述:實(shí)時(shí)時(shí)鐘 REAL TIME CLKRTC W/ EPROM IN 14LD 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(shí)間格式:HH:MM:SS RTC 存儲(chǔ)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
ISL12029IVZ-T 功能描述:實(shí)時(shí)時(shí)鐘 REAL TIME CLKRTC W/ EPROM IN 14LD T 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(shí)間格式:HH:MM:SS RTC 存儲(chǔ)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
ISL12030 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Low Power RTC with 50/60 Cycle AC Input, Alarms and Daylight Savings Correction
ISL12030IBZ 功能描述:實(shí)時(shí)時(shí)鐘 REAL TIME CLK W/ EEPROM 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(shí)間格式:HH:MM:SS RTC 存儲(chǔ)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