參數(shù)資料
型號(hào)： BQ4285EP
廠商： Texas Instruments
文件頁(yè)數(shù)： 29/31頁(yè)
文件大?。?/td> 0K
描述： IC RTC W/114X8 NVSRAM 24-DIP
產(chǎn)品培訓(xùn)模塊： Clock Basics in 10 minutes or less
標(biāo)準(zhǔn)包裝： 15
類型： 時(shí)鐘/日歷
特點(diǎn)： 警報(bào)器，夏令時(shí)，閏年，NVSRAM，方波輸出
存儲(chǔ)容量： 114B
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： 并聯(lián)
電源電壓： 4.5 V ~ 5.5 V
電壓 - 電源，電池： 2.5 V ~ 4 V
工作溫度： 0°C ~ 70°C
安裝類型： 通孔
封裝/外殼： 24-DIP（0.600"，15.24mm）
供應(yīng)商設(shè)備封裝： 24-PDIP
包裝： 管件
產(chǎn)品目錄頁(yè)面： 1076 (CN2011-ZH PDF)
其它名稱： 296-6525-5
Alarm Interrupt
The alarm interrupt request is valid in battery-backup
mode, providing a “wake-up” capability. During each up-
date cycle, the RTC compares the hours, minutes, and
seconds bytes with the three corresponding alarm bytes.
If a match of all bytes is found, the alarm interrupt
event flag bit, AF in register C, is set to 1. If the alarm
event is enabled, an interrupt request is generated.
An alarm byte may be removed from the comparison by
setting it to a “don’t care” state. An alarm byte is set to a
“don’t care” state by writinga1toeachofitstwo most-
significant bits. A “don’t care” state may be used to select
the frequency of alarm interrupt events as follows:
n
If none of the three alarm bytes is “don’t care,” the
frequency is once per day, when hours, minutes, and
seconds match.
n
If only the hour alarm byte is “don’t care,” the
frequency is once per hour, when minutes and
seconds match.
n
If only the hour and minute alarm bytes are “don’t care,”
the frequency is once per minute, when seconds match.
n
If the hour, minute, and second alarm bytes are
“don’t care,” the frequency is once per second.
Update Cycle Interrupt
The update cycle ended flag bit (UF) in register C is set to
a 1 at the end of an update cycle. If the update interrupt
enable bit (UIE) of register B is 1, and the update transfer
inhibit bit (UTI) in register B is 0, then an interrupt re-
quest is generated at the end of each update cycle.
Accessing RTC bytes
Time and calendar bytes read during an update cycle
may be in error. Three methods to access the time and
calendar bytes without ambiguity are:
n
Enable the update interrupt event to generate
interrupt requests at the end of the update cycle.
The interrupt handler has a maximum of 999ms to
access the clock bytes before the next update cycle
begins (see Figure 3).
n
Poll the update-in-progress bit (UIP) in register A. If
UIP = 0, the polling routine has a minimum of tBUC
time to access the clock bytes (see Figure 3).
n
Use
the
periodic
interrupt
event
to
generate
interrupt requests every tPI time, such that UIP = 1
always occurs between the periodic interrupts. The
interrupt handler will have a minimum of
tPI/2 +
tBUC time to access the clock bytes (see Figure 3).
Oscillator Control
When power is first applied to the bq4285E/L and VCC is
above VPFD, the internal oscillator and frequency divider
are turned on by writing a 010 pattern to bits 4 through 6
of register A. A pattern of 011 behaves as 010 but addi-
tionally transforms register C into a read/write register.
This allows the 32.768kHz output on the square wave pin
to be turned on. A pattern of 11X turns the oscillator on,
but keeps the frequency divider disabled. Any other pat-
tern to these bits keeps the oscillator off.
7
bq4285E/L
Figure 3. Update-Ended/Periodic Interrupt Relationship
相關(guān)PDF資料
PDF描述
BQ4847YMT IC RTC W/NVSRAM CONTROL T-MOD
BU2280FV-E2 IC CLOCK GEN DVD-VIDEO SSOP-B24
BU2363FV-E2 IC CLOCK GEN DVD-VIDEO SSOP-B16
BU2365FV-E2 IC CLOCK GEN W/VCXO SSOP-B24
BU2505FV-E2 IC DAC 10BIT 10-CHAN SSOP-B20
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
BQ4285ES 制造商:未知廠家 制造商全稱:未知廠家 功能描述:
BQ4285L 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Enhanced RTC With NVRAM Control
BQ4285LP 制造商:TI 制造商全稱:Texas Instruments 功能描述:Enhanced RTC With NVRAM Control
BQ4285LQ 制造商:未知廠家 制造商全稱:未知廠家 功能描述:
BQ4285LS 制造商:Rochester Electronics LLC 功能描述:- Bulk
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*