- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄45050 > M41T93RQA6F (STMICROELECTRONICS) 1 TIMER(S), REAL TIME CLOCK, PQCC16 PDF資料下載
參數(shù)資料
| 型號： | M41T93RQA6F |
| 廠商： | STMICROELECTRONICS |
| 元件分類： | 時鐘/數(shù)據(jù)恢復及定時提取 |
| 英文描述： | 1 TIMER(S), REAL TIME CLOCK, PQCC16 |
| 封裝： | 4 X 4 MM, ROHS COMPLIANT, QFN-16 |
| 文件頁數(shù)： | 8/49頁 |
| 文件大小： | 719K |
| 代理商： | M41T93RQA6F |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁當前第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁
Clock operation
M41T93
Doc ID 12615 Rev 5
3
Clock operation
The M41T93 is driven by a quartz-controlled oscillator with a nominal frequency of
32.768 kHz. 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.
The 8-byte clock register (see Table 3 on page 18) is used to both set the clock and to read
the date and time from the clock, in binary coded decimal format. Tenths/hundredths of
seconds, seconds, minutes, and hours are contained within the first four registers.
Bit D7 of register 01h contains the STOP bit (ST). Setting this bit to a '1' will cause the
oscillator to stop. When reset to a '0' the oscillator restarts within one second (typical).
Note:
Upon initial power-up, the user should set the ST bit to a '1,' then immediately reset the ST
bit to '0.' This provides an additional “kick-start” to the oscillator circuit.
Bits D6 and D7 of clock register 03h (century/ hours register) contain the CENTURY bit 0
(CB0) and CENTURY bit 1 (CB1). Bits D0 through D2 of register 04h contain the day (day of
week). Registers 05h, 06h, and 07h contain the date (day of month), month, and years. The
ninth clock register is the digital calibration register, while the analog calibration register is
found at address 12h (these are both described in the clock calibration section). Bit D7 of
register 09h (watchdog register) contains the oscillator fail interrupt enable bit (OFIE). When
the user sets this bit to '1,' any condition which sets the oscillator fail bit (OF) (see Oscillator
fail detection on page 33) will also generate an interrupt output.
Note:
A WRITE to ANY location within the first eight bytes of the clock register (00h-07h),
including the ST bit and CB0-CB1 bits will result in an update of the system clock and a
reset of the divider chain. This could result in an inadvertent change of the current time.
These non-clock related bits should be written prior to setting the clock, and remain
unchanged until such time as a new clock time is also written.
The eight clock registers may be read one byte at a time, or in a sequential block. Provision
has been made to assure that a clock update does not occur while any of the eight clock
addresses are being read. If a clock address is being read, an update of the clock registers
will be halted. This will prevent a transition of data during the READ.
3.1
Power-down time-stamp
When a power failure occurs, the halt update bit (HT) will automatically be set to a “1”. This
will prevent the clock from updating the clock/control registers, and will allow the user to
read the exact time of the power-down event. Resetting the HT bit to a “0” will allow the clock
to update the clock/registers with the current time. For more information, see application
note AN1572.
3.2
Clock/control register map
The M41T93 offers 32 internal registers which contain clock, calibration (digital and analog),
alarm 1 and 2, watchdog, flags, timer, and square wave. The clock registers are memory
locations which contain external (user accessible) and internal copies of the data (usually
referred to as BiPORT TIMEKEEPER cells). The external copies are independent of
internal functions except that they are updated periodically by the simultaneous transfer of
the incremented internal copy. The internal divider (or clock) chain will be reset upon the
相關PDF資料 |
PDF描述 |
|---|---|
| M41T93SQA6F | 1 TIMER(S), REAL TIME CLOCK, PQCC16 |
| M43C505-XXX-DIT | 4-BIT, MROM, 2 MHz, MICROCONTROLLER, UUC |
| M43C505-XXX-Q44 | 4-BIT, MROM, 2 MHz, MICROCONTROLLER, PQCC44 |
| M44C090-XXX-FL16 | 8-BIT, MROM, 16 MHz, MICROCONTROLLER, PDSO16 |
| M44C090-XXX-DIT | 4-BIT, MROM, 4 MHz, MICROCONTROLLER, UUC |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| M41T93RQA6F-CUT TAPE | 制造商:ST 功能描述:M41T93 Series 5.5 V Serial SPI Bus RTC With Battery Switchover -QFN-16 |
| M41T93SMY6E | 功能描述:實時時鐘 Serial SPI bus RTC 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: 安裝風格:Through Hole 封裝 / 箱體:PDIP-8 封裝:Tube |
| M41T93SMY6F | 功能描述:實時時鐘 Serial SPI bus RTC 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: 安裝風格:Through Hole 封裝 / 箱體:PDIP-8 封裝:Tube |
| M41T93SQA6E | 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Serial SPI bus RTC with battery switchover |
| M41T93SQA6F | 功能描述:實時時鐘 Serial SPI bus RTC 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: 安裝風格:Through Hole 封裝 / 箱體:PDIP-8 封裝:Tube |
發(fā)布緊急采購，3分鐘左右您將得到回復。