- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄30731 > LC72705E SPECIALTY CONSUMER CIRCUIT, PQFP44 PDF資料下載
參數(shù)資料
| 型號： | LC72705E |
| 元件分類： | 消費(fèi)家電 |
| 英文描述： | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
| 封裝： | QFP-44 |
| 文件頁數(shù)： | 4/14頁 |
| 文件大小： | 165K |
| 代理商： | LC72705E |
Notes on Output Data Selection During Tuning (Provided for reference purposes)
A tuning system is required in an FM multiplex broadcast reception system. However, applications must perform the
following processing if it is unacceptable for the IC to output data for the previous station after tuning a new station.
Set bit 4 (SYNC RST) in the control register during tuning to set the synchronization circuit to the unsynchronized state.
If bit 5 (INT) in the control register is enabled, do not use the post-vertical correction output (data for which bit 7 in the
status flag CNT1 is 1) until frame synchronization is re-established.
Of the DARC FM multiplex processing, this IC performs the processing through error correction (layer 2) without
requiring any special control operations. The IC itself is not able to recognize whether the content of the received data
has changed or whether the system has been tuned to another station. Therefore the application system must use the
above procedure to command the IC not to output the old data and only to output the new data. The synchronization
relationship between the stations is also problematic; although it is rare that the frames of the previous station and the
next station would be synchronized, applications must also perform the processing described above to cancel the frame
synchronization forward protection period.
Differences in Data Output between this IC and the LC72700E (Provided for reference purposes)
The LC72700E provided all data that could be provided to the microcontroller in the later stages of the system, and was
designed so that the microcontroller was required to decide whether to accept or discard the data by checking the status
output. For example, a received data packet could be output as post-horizontal correction data and then again, a few
seconds later, could be output as post-vertical correction data. Data with no errors, or data that could be corrected by
horizontal correction was output twice as identical data. This IC implements the conditions shown on page 10
(in “Notes on Post Error Correction Output Data”) concerning data with no errors. Stated simply, this IC does not output
data unnecessarily. For example, the INT signal will not be output for data from a received station that is not
broadcasting multiplexed data. Also, under good reception conditions where there are no errors, there will be no post-
vertical correction output and the INT signal period will be 18 ms.
There are cases where it may become impossible to acquire the data if the microcontroller software includes the data
acquisition conditions required for the LC72700E. For example, this problem may occur if the software was designed to
only use the post-vertical correction output. Since this IC does not output the same data twice and does not output bad
data at all, applications do not need to select from the input data if they simply acquire all data that starts at every INT
signal. (In other words, it can be also said that this IC does not generate any unnecessary interrupt signals.) To set up this
IC to provide the same output format as that of the LC72700E, applications must set bit 5 (INT MODE) in the control
register to 1. Note that this IC is added a control function that causes the IC not to output post-vertical correction data if
the vertical correction operation was not executed. Since this control function is not influenced by the INT MOVE flag,
post-vertical correction output is not provided during error-free reception even if the INT MOVE flag was set. Thus care
is required in application software design.
No. 5744-12/14
LC72705E
Figure 3 Timing of Data Reception and Block Synchronization Data Output
Figure 4 Vertical Correction Data Output Timing
Reception data
Packet (N – 1)
Packet data N
Packet (N + 1)
Output period for packet data (N – 1)
Period that data cannot be
guaranteed
Output of packet data N
Frame N – 1
Frame N
Reception
block number
BIC period
Output period for the post-vertical correction
data from the previous frame
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LC72706E | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
| LC72707E | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
| LC72708E | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
| LC72708E | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
| LC72709E | SPECIALTY CONSUMER CIRCUIT, PQFP44 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LC72706 | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:FM Multiplex Receiver IC Supporting All Worldwide Standards |
| LC72706E | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:FM Multiplex Receiver IC Supporting All Worldwide Standards |
| LC72707 | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:FM Multiplex Receiver IC Supporting All Worldwide Standards |
| LC72707E | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:FM Multiplex Receiver IC Supporting All Worldwide Standards |
| LC72708 | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:FM Multiplex Broadcast Reception IC for Mobile VICS Systems |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。